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1.
Brain ; 145(10): 3622-3636, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-35858675

RESUMO

The protein alpha-synuclein is predominantly expressed in neurons and is associated with neurodegenerative diseases like Parkinson's disease and dementia with Lewy bodies. However, the normal function of alpha-synuclein in neurons is not clearly defined. We have previously shown that mice lacking alpha-synuclein expression exhibit markedly increased viral growth in the brain, increased mortality and increased neuronal cell death, implicating alpha-synuclein in the neuronal innate immune response. To investigate the mechanism of alpha-synuclein-induced immune responses to viral infections in the brain, we challenged alpha-synuclein knockout mice and human alpha-synuclein knockout dopaminergic neurons with RNA virus infection and discovered that alpha-synuclein is required for neuronal expression of interferon-stimulated genes. Furthermore, human alpha-synuclein knockout neurons treated with type 1 interferon failed to induce a broad range of interferon stimulated genes, implying that alpha-synuclein interacts with type 1 interferon signalling. We next found that alpha-synuclein accumulates in the nucleus of interferon-treated human neurons after interferon treatment and we demonstrated that interferon-mediated phosphorylation of STAT2 is dependent on alpha-synuclein expression in human neurons. Next, we found that activated STAT2 co-localizes with alpha-synuclein following type 1 interferon stimulation in neurons. Finally, we found that brain tissue from patients with viral encephalitis expresses increased levels of phospho-serine129 alpha-synuclein in neurons. Taken together, our results show that alpha-synuclein expression supports neuron-specific interferon responses by localizing to the nucleus, supporting STAT2 activation, co-localizing with phosphorylated STAT2 in neurons and supporting expression of interferon-stimulated genes. These data provide a novel mechanism that links interferon activation and alpha-synuclein function in neurons.


Assuntos
Encéfalo , Neurônios Dopaminérgicos , Interferons , alfa-Sinucleína , Animais , Humanos , Camundongos , alfa-Sinucleína/metabolismo , Encéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Interferons/metabolismo , Corpos de Lewy/metabolismo , Camundongos Knockout
2.
J Res Natl Inst Stand Technol ; 126: 126053, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-39081638

RESUMO

Keyphrase extraction is an important facet of annotation tools that offer the provision of the metadata necessary for technical language processing (TLP). Because TLP imposes additional requirements on typical natural language processing (NLP) methods, we examined TLP keyphrase extraction through the lens of a hypothetical toolkit which consists of a combination of text features and classifers suitable for use in low-resource TLP applications. We compared two approaches for keyphrase extraction: The frst which applied our toolkit-based methods that used only distributional features of words and phrases, and the second was the Maui automatic topic indexer, a well-known academic method. Performance was measured against two collections of technical literature: 1153 articles from Journal of Chemical Thermodynamics (JCT) curated by the National Institute of Standards and Technology Thermodynamics Research Center (TRC) and 244 articles from Task 5 of the Workshop on Semantic Evaluation (SemEval). Both collections have author-provided keyphrases available; the SemEval articles also have reader-provided keyphrases. Our fndings indicate that our toolkit approach was competitive with Maui when author-provided keyphrases were frst removed from the text. For the TRC-JCT articles, the Maui automatic topic indexer reported an F-measure of 29.4 % while our toolkit approach obtained an F-measure of 28.2 %. For the SemEval articles, our toolkit approach using a Naïve Bayes classifer resulted in an F-measure of 20.8 %, which outperformed Maui's F-measure of 18.8 %.

3.
Crit Rev Food Sci Nutr ; 58(17): 2867-2881, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28662339

RESUMO

Grain sorghum is an important staple food crop grown globally while sweet sorghum is increasingly considered as a promising biofuel feedstock. Biofuels are the major economic products from the processing of large quantities of biomass, which is currently being utilized to make value-added products in the biorefinery approach. To date, these value-added products are typically commodity chemicals and waste materials used in agriculture. However, there are opportunities to generate high-value bioactive compounds from sorghum grain and biomass. Chronic diseases, such as cancers, are the top causes for morbidity and mortality in developed nations and are promoted by inflammation and oxidative stress. Globally, colorectal cancer results in approximately one-half million deaths annually. It is estimated that as much as 80% of colorectal cancer cases can be attributed to environmental and dietary factors. The sorghum grain and ligno-cellulosic biomass generated for biofuel production has been reported to be high in bioactive compounds, including phenolic acids and flavonoids, with antioxidant and anti-inflammatory properties. This review focuses on the bioactive compounds of grain and sweet sorghum (Sorghum bicolor L. Moench), for their anti-inflammatory, antioxidant, anti-colon cancer, and immune modulator functions. The review summarizes previous efforts to identify and quantify bioactive compounds in sorghum and documents their anti-cancer biological activities. Finally, this review discusses bioactive compound extraction methodologies and technologies as well as considerations for incorporating these technologies into current biorefining practices.


Assuntos
Grão Comestível/química , Compostos Fitoquímicos/farmacologia , Sorghum/fisiologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/química
4.
Science ; 354(6316): 1148-1152, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27934765

RESUMO

The outbreak of Zika virus (ZIKV) and associated fetal microcephaly mandates efforts to understand the molecular processes of infection. Related flaviviruses produce noncoding subgenomic flaviviral RNAs (sfRNAs) that are linked to pathogenicity in fetal mice. These viruses make sfRNAs by co-opting a cellular exonuclease via structured RNAs called xrRNAs. We found that ZIKV-infected monkey and human epithelial cells, mouse neurons, and mosquito cells produce sfRNAs. The RNA structure that is responsible for ZIKV sfRNA production forms a complex fold that is likely found in many pathogenic flaviviruses. Mutations that disrupt the structure affect exonuclease resistance in vitro and sfRNA formation during infection. The complete ZIKV xrRNA structure clarifies the mechanism of exonuclease resistance and identifies features that may modulate function in diverse flaviviruses.


Assuntos
Exorribonucleases/química , RNA não Traduzido/química , RNA Viral/química , Infecção por Zika virus/virologia , Zika virus/metabolismo , Animais , Chlorocebus aethiops , Culicidae/virologia , Células Epiteliais/virologia , Exorribonucleases/genética , Humanos , Camundongos , Mutação , Neurônios/virologia , Conformação de Ácido Nucleico , RNA não Traduzido/genética , RNA Viral/genética , Células Vero , Zika virus/genética
5.
Viruses ; 8(10)2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27763553

RESUMO

West Nile virus (WNV) is a (+) sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5' cap with 2'-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1) for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein (4EBP) pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E) interaction and eukaryotic initiation factor 4F (eIF4F) complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6) and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome.


Assuntos
Proteínas de Transporte/metabolismo , Interações Hospedeiro-Patógeno , Fosfoproteínas/metabolismo , Transdução de Sinais , Proteínas Virais/biossíntese , Replicação Viral , Vírus do Nilo Ocidental/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Fatores de Iniciação em Eucariotos , Deleção de Genes , Camundongos , Camundongos Knockout , Fosfoproteínas/deficiência , Proteínas Quinases S6 Ribossômicas 70-kDa/deficiência , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo
6.
DNA Cell Biol ; 35(11): 643-645, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27631132

RESUMO

Alpha-synuclein (α-syn) is a highly conserved protein encoded by the SNCA gene and is expressed uniquely in neurons of both the central and peripheral nervous systems (CNS and PNS). α-Syn is known to cause sporadic and familial forms of Parkinson's disease (PD). However, the role for neuronal expression of α-syn in the first place remains unknown. We review and discuss recently published work that suggests a novel role for α-syn expression in neurons as a restriction factor that inhibits virus transmission from the PNS to the CNS. The potential new role for α-syn expression as a virus inhibitor may provide new approaches to understand the pathogenesis of PD and provide novel approaches to prevent and treat this common neurodegenerative disease.


Assuntos
Sistema Nervoso Central/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Sistema Nervoso Periférico/metabolismo , alfa-Sinucleína/metabolismo , Animais , Sistema Nervoso Central/virologia , Expressão Gênica/fisiologia , Humanos , Doenças Neurodegenerativas/virologia , Neurônios/virologia , Sistema Nervoso Periférico/virologia
7.
JAMA Neurol ; 73(7): 875-9, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27183312

RESUMO

IMPORTANCE: Zika virus (ZIKV) is an emerging arthropod-borne virus (arbovirus) in the genus Flavivirus that has caused a widespread outbreak of febrile illness, is associated with neurological disease, and has spread across the Pacific to the Americas in a short period. OBSERVATIONS: In this review, we discuss what is currently known about ZIKV, neuroimmunologic complications, and the impact on global human health. Zika virus spread across Africa and Asia in part owing to unique genomic evolutionary conditions and pressures resulting in specific human disease manifestations, complications, and pathogenesis. Recent data suggest that acute ZIKV infection in pregnant women may result in acute infection of fetal tissue and brain tissue, causing microcephaly and potentially severe debilitation of the infant or even death of the fetus. Cases of acute ZIKV are also associated with Guillain-Barré syndrome. With the increased number of cases, new complications such as ocular involvement and sexual transmission have been reported. CONCLUSIONS AND RELEVANCE: Zika virus is an emerging viral pathogen with significant consequences on human health throughout the world. Ongoing research into this pathogen is urgently needed to produce viable vaccine and therapeutic options.


Assuntos
Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/virologia , Infecção por Zika virus/complicações , Zika virus/patogenicidade , Animais , Feminino , Humanos , Masculino , Gravidez
8.
Open Forum Infect Dis ; 3(1): ofv182, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26730392

RESUMO

Background. West Nile virus (WNV) infection in humans can result in severe, acute encephalitis typically involving subcortical gray matter brain regions. West Nile virus replication within specific human brain regions from a human case of acute encephalitis has not been studied. Methods. We describe a fatal case of WNV encephalitis in which we obtained tissue from specific brain regions at autopsy to evaluate viral-host interactions using next-generation sequencing and immunohistochemistry analysis. Results. We found that WNV populations in the injured subcortical brain regions exhibited increased amino acid variation and increased expression of specific interferon genes compared with cortical tissues despite similar viral burden. Conclusions. These observational, patient-based data suggest that neuronal injury and the strength of viral selection pressure may be associated with the level of the innate immune responses. Further studies in human and animal models evaluating the role of innate immune responses on injury patterns and viral selection pressure are needed.

9.
J Virol ; 90(6): 2767-82, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26719256

RESUMO

UNLABELLED: We have discovered that native, neuronal expression of alpha-synuclein (Asyn) inhibits viral infection, injury, and disease in the central nervous system (CNS). Enveloped RNA viruses, such as West Nile virus (WNV), invade the CNS and cause encephalitis, yet little is known about the innate neuron-specific inhibitors of viral infections in the CNS. Following WNV infection of primary neurons, we found that Asyn protein expression is increased. The infectious titer of WNV and Venezuelan equine encephalitis virus (VEEV) TC83 in the brains of Asyn-knockout mice exhibited a mean increase of 10(4.5) infectious viral particles compared to the titers in wild-type and heterozygote littermates. Asyn-knockout mice also exhibited significantly increased virus-induced mortality compared to Asyn heterozygote or homozygote control mice. Virus-induced Asyn localized to perinuclear, neuronal regions expressing viral envelope protein and the endoplasmic reticulum (ER)-associated trafficking protein Rab1. In Asyn-knockout primary neuronal cultures, the levels of expression of ER signaling pathways, known to support WNV replication, were significantly elevated before and during viral infection compared to those in Asyn-expressing primary neuronal cultures. We propose a model in which virus-induced Asyn localizes to ER-derived membranes, modulates virus-induced ER stress signaling, and inhibits viral replication, growth, and injury in the CNS. These data provide a novel and important functional role for the expression of native alpha-synuclein, a protein that is closely associated with the development of Parkinson's disease. IMPORTANCE: Neuroinvasive viruses such as West Nile virus are able to infect neurons and cause severe disease, such as encephalitis, or infection of brain tissue. Following viral infection in the central nervous system, only select neurons are infected, implying that neurons exhibit innate resistance to viral infections. We discovered that native neuronal expression of alpha-synuclein inhibited viral infection in the central nervous system. When the gene for alpha-synuclein was deleted, mice exhibited significantly decreased survival, markedly increased viral growth in the brain, and evidence of increased neuron injury. Virus-induced alpha-synuclein localized to intracellular neuron membranes, and in the absence of alpha-synuclein expression, specific endoplasmic reticulum stress signaling events were significantly increased. We describe a new neuron-specific inhibitor of viral infections in the central nervous system. Given the importance of alpha-synuclein as a cause of Parkinson's disease, these data also ascribe a novel functional role for the native expression of alpha-synuclein in the CNS.


Assuntos
Encéfalo/imunologia , Vírus da Encefalite Equina Venezuelana/imunologia , Expressão Gênica , Imunidade Inata , Infecções por Vírus de RNA/prevenção & controle , Vírus do Nilo Ocidental/imunologia , alfa-Sinucleína/biossíntese , Animais , Encéfalo/virologia , Células Cultivadas , Vírus da Encefalite Equina Venezuelana/isolamento & purificação , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/imunologia , Neurônios/virologia , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/virologia , Análise de Sobrevida , Vírus do Nilo Ocidental/isolamento & purificação
10.
J Agric Food Chem ; 62(14): 3150-3159, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24655033

RESUMO

There is a growing interest in the utilization of sweet sorghum as a renewable resource for biofuels. During the biofuel production process, large quantities of biomass are generated, creating a rich source of bioactive compounds. However, knowledge of sweet sorghum stalk is lacking. We measured the phenolic content (Folin-Ciocalteu assay), antioxidant activity (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) assay), and phytochemical composition (LC-MS) in both the pith and dermal layer of the stalk. We further tested the antiproliferative (5-bromo-2'- deoxyuridine assay) and proapoptotic (terminal deoxynucleotidyl transferase dUTP nick end labeling assay) activities of these extracts using HCT116 cells and colon cancer stem cells (CCSCs) with and without the tumor suppressor gene p53. For the first time, we show that the dermal layer extract of sweet sorghum contains more of the 3-deoxyanthocyanidins apigeninidin and luteolinidin than the pith, and this is associated with more anticancer activity. Furthermore, luteolinidin suppressed CCSC proliferation more than apigeninidin. In addition to being renewable biofuel, sweet sorghum may also serve as a source of health-promoting compounds.

11.
J Food Sci ; 77(8): H176-83, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22747948

RESUMO

UNLABELLED: The human health benefits from consumption of cranberry products have been associated with the fruits' unique flavonoid composition, including a complex profile of anthocyanins and proanthocyanidins. However, when processed by techniques such as pressing, canning, concentrating, or drying, a number of these natural components may be compromised or inactivated due to physical separation, thermal degradation, or oxidation. Fresh cranberries were compared to freeze-dried berries and individual fruit tissues (skin and peeled fruit). Products examined included cranberry juices (commercial and prepared from concentrate), cranberry sauces (commercial and homemade), and sweetened-dried cranberries (commercial). Freeze-drying resulted in no detectable losses of anthocyanins or proanthocyanidins from cranberry fruits. Anthocyanins were localized in the skin. Proanthocyanins were higher in the skin than in the flesh, with the exception of procyanidin A-2 dimer which was concentrated in the flesh. Anthocyanins were significantly higher in not-from-concentrate juice than in reconstituted juice from concentrate (8.3 mg and 4.2 mg/100 mL, respectively). Similarly, proanthocyanidins were markedly higher in not-from-concentrate juice compared to juice from concentrate (23.0 mg and 8.9 mg/100 mL, respectively). Homemade sauce contained far higher anthocyanins and proanthocyanidins (15.9 and 87.9 mg/100 g, respectively) than canned sauces processed with whole berries (9.6 and 54.4 mg/100 g, respectively) or jelled-type (1.1 and 16 mg/100 g, respectively). Sweetened-dried cranberries were quite low in anthocyanins (7.9 mg/100 g), but they still retained considerable proanthocyanidins (64.2 mg/100 g). Commercially processed products contained significantly lower levels of polyphenols as compared to fresh and home-processed preparations. Anthocyanins were more sensitive to degradation than proanthocyanidins. PRACTICAL APPLICATION: As cranberry juices and other products are increasingly consumed for their recognized health benefits (including prophylaxis against urinary tract infection), it is relevant to consider how various degrees of commercial and home processing can alter innate levels of the biologically active flavonoids (especially anthocyanins and proanthocyanidins) characteristic to the intact fruits.


Assuntos
Antocianinas/análise , Bebidas , Biflavonoides/análise , Catequina/análise , Flavonoides/análise , Proantocianidinas/análise , Vaccinium macrocarpon/química , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos/métodos , Liofilização , Frutas/química , Extratos Vegetais/análise
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