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1.
Mol Cell ; 69(6): 923-937.e8, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29547721

RESUMO

Dietary supplements such as vitamins and minerals are widely used in the hope of improving health but may have unidentified risks and side effects. In particular, a pathogenic link between dietary supplements and specific oncogenes remains unknown. Here we report that chondroitin-4-sulfate (CHSA), a natural glycosaminoglycan approved as a dietary supplement used for osteoarthritis, selectively promotes the tumor growth potential of BRAF V600E-expressing human melanoma cells in patient- and cell line-derived xenograft mice and confers resistance to BRAF inhibitors. Mechanistically, chondroitin sulfate glucuronyltransferase (CSGlcA-T) signals through its product CHSA to enhance casein kinase 2 (CK2)-PTEN binding and consequent phosphorylation and inhibition of PTEN, which requires CHSA chains and is essential to sustain AKT activation in BRAF V600E-expressing melanoma cells. However, this CHSA-dependent PTEN inhibition is dispensable in cancer cells expressing mutant NRAS or PI3KCA, which directly activate the PI3K-AKT pathway. These results suggest that dietary supplements may exhibit oncogene-dependent pro-tumor effects.


Assuntos
Carcinógenos/toxicidade , Transformação Celular Neoplásica/genética , Sulfatos de Condroitina/toxicidade , Suplementos Nutricionais/toxicidade , Melanoma/induzido quimicamente , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/induzido quimicamente , Animais , Antinematódeos/farmacologia , Caseína Quinase II/metabolismo , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , GTP Fosfo-Hidrolases/genética , Células HEK293 , Células HT29 , Humanos , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Melanoma/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos Transgênicos , Células NIH 3T3 , Proteínas Nucleares/genética , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Nucleic Acids Res ; 52(14): e62, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38922688

RESUMO

Genome-level clonal decomposition of a single specimen has been widely studied; however, it is mostly limited to cancer research. In this study, we developed a new algorithm CLEMENT, which conducts accurate decomposition and reconstruction of multiple subclones in genome sequencing of non-tumor (normal) samples. CLEMENT employs the Expectation-Maximization (EM) algorithm with optimization strategies specific to non-tumor subclones, including false variant call identification, non-disparate clone fuzzy clustering, and clonal allele fraction confinement. In the simulation and in vitro cell line mixture data, CLEMENT outperformed current cancer decomposition algorithms in estimating the number of clones (root-mean-square-error = 0.58-0.78 versus 1.43-3.34) and in the variant-clone membership agreement (∼85.5% versus 70.1-76.7%). Additional testing on human multi-clonal normal tissue sequencing confirmed the accurate identification of subclones that originated from different cell types. Clone-level analysis, including mutational burden and signatures, provided a new understanding of normal-tissue composition. We expect that CLEMENT will serve as a crucial tool in the currently emerging field of non-tumor genome analysis.


Assuntos
Algoritmos , Genômica , Humanos , Genômica/métodos , Neoplasias/genética , Mutação , Genoma Humano , Células Clonais
3.
Proc Natl Acad Sci U S A ; 120(43): e2221859120, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37844250

RESUMO

Metastatic cancer accounts for 90% of all cancer-related deaths and continues to be one of the toughest challenges in cancer treatment. A growing body of data indicates that S100A9, a major regulator of inflammation, plays a central role in cancer progression and metastasis, particularly in the lungs, where S100A9 forms a premetastatic niche. Thus, we developed a vaccine against S100A9 derived from plant viruses and virus-like particles. Using multiple tumor mouse models, we demonstrate the effectiveness of the S100A9 vaccine candidates in preventing tumor seeding within the lungs and outgrowth of metastatic disease. The elicited antibodies showed high specificity toward S100A9 without cross-reactivity toward S100A8, another member of the S100A family. When tested in metastatic mouse models of breast cancer and melanoma, the vaccines significantly reduced lung tumor nodules after intravenous challenge or postsurgical removal of the primary tumor. Mechanistically, the vaccines reduce the levels of S100A9 within the lungs and sera, thereby increasing the expression of immunostimulatory cytokines with antitumor function [(interleukin) IL-12 and interferonγ] while reducing levels of immunosuppressive cytokines (IL-10 and transforming growth factorß). This also correlated with decreased myeloid-derived suppressor cell populations within the lungs. This work has wide-ranging impact, as S100A9 is overexpressed in multiple cancers and linked with poor prognosis in cancer patients. The data presented lay the foundation for the development of therapies and vaccines targeting S100A9 to prevent metastasis.


Assuntos
Neoplasias Pulmonares , Vacinas Virais , Humanos , Camundongos , Animais , Calgranulina B/metabolismo , Neoplasias Pulmonares/prevenção & controle , Calgranulina A/metabolismo , Pulmão/patologia , Citocinas/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(17): e2208718120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068231

RESUMO

The hemagglutinin (HA) stem region is a major target of universal influenza vaccine efforts owing to the presence of highly conserved epitopes across multiple influenza A virus (IAV) strains and subtypes. To explore the potential impact of vaccine-induced immunity targeting the HA stem, we examined the fitness effects of viral escape from stem-binding broadly neutralizing antibodies (stem-bnAbs). Recombinant viruses containing each individual antibody escape substitution showed diminished replication compared to wild-type virus, indicating that stem-bnAb escape incurred fitness costs. A second-site mutation in the HA head domain (N129D; H1 numbering) reduced the fitness effects observed in primary cell cultures and likely enabled the selection of escape mutations. Functionally, this putative permissive mutation increased HA avidity for its receptor. These results suggest a mechanism of epistasis in IAV, wherein modulating the efficiency of attachment eases evolutionary constraints imposed by the requirement for membrane fusion. Taken together, the data indicate that viral escape from stem-bnAbs is costly but highlights the potential for epistatic interactions to enable evolution within the functionally constrained HA stem domain.


Assuntos
Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes/genética , Epistasia Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vacinas contra Influenza/genética , Hemaglutininas , Influenza Humana/genética , Influenza Humana/prevenção & controle
5.
Plant J ; 120(1): 187-198, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39133829

RESUMO

Polycomb group (PcG) proteins are essential gene repressors in higher eukaryotes. However, how PcG proteins mediate transcriptional regulation of specific genes remains unknown. LIKE HETEROCHROMATIN PROTEIN 1 (LHP1), as a component of Polycomb Repression Complexes (PRC), epigenetically mediates several plant developmental processes together with PcG proteins. We observed physical interaction between MYB73 and LHP1 in vitro and in vivo. Genetic analysis indicated that myb73 mutants showed slightly late flowering, and the lhp1-3 myb73-2 double mutant exhibited delayed flowering and downregulated FT expression compared to lhp1-3. Chromatin immunoprecipitation and yeast one-hybrid assays revealed that MYB73 preferentially binds to the FT promoter. Additionally, our protoplast transient assays demonstrated that MYB73 activates to the FT promoter. Interestingly, the LHP1-MYB73 interaction is necessary to repress the FT promoter, suggesting that the LHP1-MYB73 interaction prevents FT activation by MYB73 in Arabidopsis. Our results show an example in which a chromatin regulator affects transcriptional regulation by negatively regulating a transcription factor through direct interaction.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Regiões Promotoras Genéticas , Fatores de Transcrição , Ativação Transcricional , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
6.
PLoS Pathog ; 18(9): e1010865, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121893

RESUMO

For diverse viruses, cellular infection with single vs. multiple virions can yield distinct biological outcomes. We previously found that influenza A/guinea fowl/Hong Kong/WF10/99 (H9N2) virus (GFHK99) displays a particularly high reliance on multiple infection in mammalian cells. Here, we sought to uncover the viral processes underlying this phenotype. We found that the need for multiple infection maps to amino acid 26K of the viral PA protein. PA 26K suppresses endonuclease activity and viral transcription, specifically within cells infected at low multiplicity. In the context of the higher functioning PA 26E, inhibition of PA using baloxavir acid augments reliance on multiple infection. Together, these data suggest a model in which sub-optimal activity of the GFHK99 endonuclease results in inefficient priming of viral transcription, an insufficiency which can be overcome with the introduction of additional viral ribonucleoprotein templates to the cell. More broadly, the finding that deficiency in a core viral function is ameliorated through multiple infection suggests that the fitness effects of many viral mutations are likely to be modulated by multiplicity of infection, such that the shape of fitness landscapes varies with viral densities.


Assuntos
Coinfecção , Vírus da Influenza A Subtipo H9N2 , Influenza Humana , Aminoácidos , Animais , Endonucleases/metabolismo , Humanos , Vírus da Influenza A Subtipo H9N2/genética , Influenza Humana/genética , Mamíferos , Ribonucleoproteínas/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Transcrição Viral
7.
PLoS Pathog ; 18(3): e1010181, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35333914

RESUMO

Transmission efficiency is a critical factor determining the size of an outbreak of infectious disease. Indeed, the propensity of SARS-CoV-2 to transmit among humans precipitated and continues to sustain the COVID-19 pandemic. Nevertheless, the number of new cases among contacts is highly variable and underlying reasons for wide-ranging transmission outcomes remain unclear. Here, we evaluated viral spread in golden Syrian hamsters to define the impact of temporal and environmental conditions on the efficiency of SARS-CoV-2 transmission through the air. Our data show that exposure periods as brief as one hour are sufficient to support robust transmission. However, the timing after infection is critical for transmission success, with the highest frequency of transmission to contacts occurring at times of peak viral load in the donor animals. Relative humidity and temperature had no detectable impact on transmission when exposures were carried out with optimal timing and high inoculation dose. However, contrary to expectation, trends observed with sub-optimal exposure timing and lower inoculation dose suggest improved transmission at high relative humidity or high temperature. In sum, among the conditions tested, our data reveal the timing of exposure to be the strongest determinant of SARS-CoV-2 transmission success and implicate viral load as an important driver of transmission.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , Mesocricetus , Pandemias , Carga Viral
8.
Cardiovasc Diabetol ; 23(1): 5, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172896

RESUMO

BACKGROUND: It is unknown whether high hemoglobin A1c (HbA1c) is associated with increases in the risk of cardiovascular disease among individuals with elevated genetic susceptibility. We aimed to investigate the association between HbA1c and atrial fibrillation (AF), coronary artery disease (CAD), and ischemic stroke according to the polygenic risk score (PRS). METHODS: The UK Biobank cohort included 502,442 participants aged 40-70 years who were recruited from 22 assessment centers across the United Kingdom from 2006 to 2010. This study included 305,605 unrelated individuals with available PRS and assessed new-onset AF, CAD, and ischemic stroke. The participants were divided into tertiles based on the validated PRS for each outcome. Within each PRS tertiles, the risks of incident events associated with HbA1c levels were investigated and compared with HbA1c < 5.7% and low PRS. Data were analyzed from November 2022 to May 2023. RESULTS: Of 305,605 individuals, 161,605 (52.9%) were female, and the mean (SD) age was 56.6 (8.1) years. During a median follow-up of 11.9 (interquartile range 11.1-12.6) years, the incidences of AF, CAD, and ischemic stroke were 4.6, 2.9 and 1.1 per 100 person-years, respectively. Compared to individuals with HbA1c < 5.7% and low PRS, individuals with HbA1c ≥ 6.5% and high PRS had a 2.67-times higher risk for AF (hazard ratio [HR], 2.67; 95% confidence interval (CI), 2.43-2.94), 5.71-times higher risk for CAD (HR, 5.71; 95% CI, 5.14-6.33) and 2.94-times higher risk for ischemic stroke (HR, 2.94; 95% CI, 2.47-3.50). In the restricted cubic spline models, while a U-shaped trend was observed between HbA1c and the risk of AF, dose-dependent increases were observed between HbA1c and the risk of CAD and ischemic stroke regardless PRS tertile. CONCLUSIONS: Our results suggest that the nature of the dose-dependent relationship between HbA1c levels and cardiovascular disease in individuals with different PRS is outcome-specific. This adds to the evidence that PRS may play a role together with glycemic status in the development of cardiovascular disease.


Assuntos
Fibrilação Atrial , Doença da Artéria Coronariana , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Masculino , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/genética , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/genética , Hemoglobinas Glicadas , Estratificação de Risco Genético , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/genética , Medição de Risco
9.
Psychol Med ; 54(2): 399-408, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37485703

RESUMO

BACKGROUND: Substantial evidence indicates structural abnormalities in the cerebral cortex of patients with schizophrenia (SCZ), although their clinical implications remain unclear. Previous case-control studies have investigated group-level differences in structural abnormalities, although the study design cannot account for interindividual differences. Recent research has focused on the association between the heterogeneity of the cerebral cortex morphometric features and clinical heterogeneity. METHODS: We used neuroimaging data from 420 healthy controls and 695 patients with SCZ from seven studies. Four cerebral cortex measures were obtained: surface area, gray matter volume, thickness, and local gyrification index. We calculated the coefficient of variation (CV) and person-based similarity index (PBSI) scores and performed group comparisons. Associations between the PBSI scores and cognitive functions were evaluated using Spearman's rho test and normative modeling. RESULTS: Patients with SCZ had a greater CV of surface area and cortical thickness than those of healthy controls. All PBSI scores across cortical measures were lower in patients with SCZ than in HCs. In the patient group, the PBSI scores for gray matter volume and all cortical measures taken together positively correlated with the full-scale IQ scores. Patients with deviant PBSI scores for gray matter volume and all cortical measures taken together had lower full-scale IQ scores than those of other patients. CONCLUSIONS: The cerebral cortex in patients with SCZ showed greater regional and global structural variability than that in healthy controls. Patients with deviant similarity of cortical structural profiles exhibited a lower general intelligence than those exhibited by the other patients.


Assuntos
Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Imageamento por Ressonância Magnética/métodos , Esquizofrenia/complicações , Córtex Cerebral/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Neuroimagem
10.
Mol Psychiatry ; 28(9): 3717-3726, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37773447

RESUMO

There are no studies investigating topological properties of resting-state fMRI (rs-fMRI) in patients who have recovered from psychosis and discontinued medication (hereafter, recovered patients [RP]). This study aimed to explore topological organization of the functional brain connectome in the RP using graph theory approach. We recruited 30 RP and 50 age and sex-matched healthy controls (HC). The RP were further divided into the subjects who were relapsed after discontinuation of antipsychotics (RP-R) and who maintained recovered state without relapse (RP-M). Using graph-based network analysis of rs-fMRI signals, global and local metrics and hub information were obtained. The robustness of the network was tested with random failure and targeted attack. As an ancillary analysis, Network-Based Statistic (NBS) was performed. Association of significant findings with psychopathology and cognitive functioning was also explored. The RP showed intact network properties in terms of global and local metrics. However, higher global functional connectivity strength and hyperconnectivity in the interconnected component were observed in the RP compared to HC. In the subgroup analysis, the RP-R were found to have lower global efficiency, longer characteristic path length and lower robustness whereas no such abnormalities were identified in the RP-M. Associations of the degree centrality of some hubs with cognitive functioning were identified in the RP-M. Even though network properties of the RP were intact, subgroup analysis revealed more altered topological organizations in the RP-R. The findings in the RP-R and RP-M may serve as network biomarkers for predicting relapse or maintained recovery after the discontinuation of antipsychotics.


Assuntos
Antipsicóticos , Conectoma , Transtornos Psicóticos , Humanos , Antipsicóticos/uso terapêutico , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Transtornos Psicóticos/tratamento farmacológico , Recidiva
11.
Mol Psychiatry ; 28(3): 1201-1209, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36494461

RESUMO

Schizophrenia (SZ) is associated with an increased risk of life-long cognitive impairments, age-related chronic disease, and premature mortality. We investigated evidence for advanced brain ageing in adult SZ patients, and whether this was associated with clinical characteristics in a prospective meta-analytic study conducted by the ENIGMA Schizophrenia Working Group. The study included data from 26 cohorts worldwide, with a total of 2803 SZ patients (mean age 34.2 years; range 18-72 years; 67% male) and 2598 healthy controls (mean age 33.8 years, range 18-73 years, 55% male). Brain-predicted age was individually estimated using a model trained on independent data based on 68 measures of cortical thickness and surface area, 7 subcortical volumes, lateral ventricular volumes and total intracranial volume, all derived from T1-weighted brain magnetic resonance imaging (MRI) scans. Deviations from a healthy brain ageing trajectory were assessed by the difference between brain-predicted age and chronological age (brain-predicted age difference [brain-PAD]). On average, SZ patients showed a higher brain-PAD of +3.55 years (95% CI: 2.91, 4.19; I2 = 57.53%) compared to controls, after adjusting for age, sex and site (Cohen's d = 0.48). Among SZ patients, brain-PAD was not associated with specific clinical characteristics (age of onset, duration of illness, symptom severity, or antipsychotic use and dose). This large-scale collaborative study suggests advanced structural brain ageing in SZ. Longitudinal studies of SZ and a range of mental and somatic health outcomes will help to further evaluate the clinical implications of increased brain-PAD and its ability to be influenced by interventions.


Assuntos
Esquizofrenia , Adulto , Humanos , Masculino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Prospectivos , Imageamento por Ressonância Magnética , Encéfalo/patologia , Envelhecimento
12.
Plant Cell Rep ; 43(2): 56, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319432

RESUMO

KEY MESSAGE: This is the first report showing anthocyanin accumulation in the soybean cotyledon via genetic transformation of a single gene. Soybean [Glycine max (L.) Merrill] contains valuable components, including anthocyanins. To enhance anthocyanin production in Korean soybean Kwangankong, we utilized the R2R3-type MYB gene (IbMYB1a), known for inducing anthocyanin pigmentation in Arabidopsis. This gene was incorporated into constructs using two promoters: the CaMV 35S promoter (P35S) and the ß-conglycinin promoter (Pß-con). Kwangankong was transformed using Agrobacterium, and the presence of IbMYB1a and Bar transgenes in T0 plants was confirmed through polymerase chain reaction (PCR), followed by gene expression validation. Visual inspection revealed that one P35S:IbMYB1a and three Pß-con:IbMYB1a lines displayed seed color change. Pß-con:IbMYB1a T1 seeds accumulated anthocyanins in cotyledon outer layers, whereas P35S:IbMYB1a and non-transgenic black soybean (Cheongja 5 and Seum) accumulated anthocyanins in the seed coat. During the germination and growth phase, T1 seedlings from Pß-con:IbMYB1a lines exhibited anthocyanin pigmentation in cotyledons for up to 1 month without growth aberrations. High-performance liquid chromatography confirmed cyanidin-3-O-glucoside as the major anthocyanin in the Pß-con:IbMYB1a line (#3). We analyzed the expression patterns of anthocyanin biosynthesis genes, chalcone synthase 7,8, chalcone isomerase 1A, flavanone 3-hydroxylase, flavanone 3'-hydroxylase, dihydroflavanol reductase 1, dihydroflavanol reductase 2, anthocyanidin synthase 2, anthocyanidin synthase 3, and UDP glucose flavonoid 3-O-glucosyltransferase in transgenic and control Kwangankong and black soybean (Cheongja 5 and Seum) seeds using quantitative real-time PCR. We conclude that the induction of gene expression in transgenic plants in comparison with Kwangankong was attributable to IbMYB1a transformation. Notably, flavanone 3-hydroxylase, flavanone 3'-hydroxylase, and dihydroflavanol reductase 1 were abundantly expressed in black soybean seed coat, distinguishing them from transgenic cotyledons.


Assuntos
Arabidopsis , Flavanonas , Glycine max/genética , Antocianinas , Cotilédone/genética , Pigmentação/genética , Oxigenases de Função Mista
13.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338917

RESUMO

Viruses have evolved sophisticated mechanisms to manipulate host cell processes and utilize intracellular organelles to facilitate their replication. These complex interactions between viruses and cellular organelles allow them to hijack the cellular machinery and impair homeostasis. Moreover, viral infection alters the cell membrane's structure and composition and induces vesicle formation to facilitate intracellular trafficking of viral components. However, the research focus has predominantly been on the immune response elicited by viruses, often overlooking the significant alterations that viruses induce in cellular organelles. Gaining a deeper understanding of these virus-induced cellular changes is crucial for elucidating the full life cycle of viruses and developing potent antiviral therapies. Exploring virus-induced cellular changes could substantially improve our understanding of viral infection mechanisms.


Assuntos
Viroses , Replicação Viral , Humanos , Organelas/ultraestrutura , Interações Hospedeiro-Patógeno
14.
Cogn Affect Behav Neurosci ; 23(2): 440-456, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36788202

RESUMO

Although the use of nondrug rewards (e.g., money) to facilitate smoking cessation is widespread, recent research has found that such rewards may be least effective when people who smoke cigarettes are tempted to do so. Specifically, among people who smoke, the neural response to nondrug rewards appears blunted when access to cigarettes is anticipated, and this blunting is linked to a decrease in willingness to refrain from smoking to earn a monetary incentive. Accordingly, methods to enhance the value of nondrug rewards may be theoretically and clinically important. The current proof-of-concept study tested if real-time fMRI neurofeedback training augments the ability to upregulate responses in reward-related brain areas relative to a no-feedback control condition in people who smoke. Adults (n = 44, age range = 20-44) who reported smoking >5 cigarettes per day completed the study. Those in the intervention group (n = 22, 5 females) were trained to upregulate brain responses using feedback of ongoing striatal activity (i.e., a dynamic "thermometer" that reflected ongoing changes of fMRI signal intensity in the striatum) in a single neurofeedback session with three training runs. The control group (n = 22, 5 females) underwent a nearly identical procedure but received no neurofeedback. Those who received neurofeedback training demonstrated significantly greater increases in striatal BOLD activation while attempting to think about something rewarding compared to controls, but this effect was present only during the first training run. Future neurofeedback research with those who smoke should explore how to make neurofeedback training more effective for the self-regulation of reward-related brain activities.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Recompensa , Mapeamento Encefálico/métodos , Fumar
15.
Bioconjug Chem ; 34(9): 1596-1605, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37611278

RESUMO

Toll-like receptors (TLRs) are promising targets in cancer immunotherapy due to their role in activating the immune system; therefore, various small-molecule TLR agonists have been tested in clinical applications. However, the clinical use of TLR agonists is hindered by their non-specific side effects and poor pharmacokinetics. To overcome these limitations, we used plant virus nanoparticles (VNPs) and bacteriophage virus-like particles (VLPs) as drug delivery systems. We conjugated TLR3 or TLR7 agonists to cowpea mosaic virus (CPMV) VNPs, cowpea chlorotic mottle virus (CCMV) VNPs, and bacteriophage Qß VLPs. The conjugation of TLR7 agonist, 2-methoxyethoxy-8-oxo-9-(4-carboxybenzyl)adenine (1V209), resulted in the potent activation of immune cells and promoted the production of pro-inflammatory cytokine interleukin 6. We found that 1V209 conjugated to CPMV, CCMV, and Qß reduced tumor growth in vivo and prolonged the survival of mice compared to those treated with free 1V209 or a simple admixture of 1V209 and viral particles. Nucleic acid-based TLR3 agonist, polyinosinic acid with polycytidylic acid (poly(I:C)), was also delivered by CPMV VNPs, resulting in enhanced mice survival. All our data suggest that coupling and co-delivery are required to enhance the anti-tumor efficacy of TLR agonists and simple mixing of the VLPs with the agonists does not confer a survival benefit. The delivery of 1V209 or poly(I:C) conjugated to VNPs/VLPs probably enhances their efficacy due to the multivalent presentation, prolongation of tumor residence time, and targeting of the innate immune cells mediated by the VNP/VLP carrier.


Assuntos
Bacteriófagos , Bromovirus , Neoplasias , Vírus de Plantas , Animais , Camundongos , Receptor 3 Toll-Like , Receptor 7 Toll-Like , Adjuvantes Imunológicos , Imunoterapia , Neoplasias/tratamento farmacológico
16.
Bioconjug Chem ; 34(1): 269-278, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36608270

RESUMO

The SARS-CoV-2 pandemic has highlighted the need for vaccines that are effective, but quickly produced. Of note, vaccines with plug-and-play capabilities that co-deliver antigen and adjuvant to the same cell have shown remarkable success. Our approach of utilizing a nitrilotriacetic acid (NTA) histidine (His)-tag chemistry with viral adjuvants incorporates both of these characteristics: plug-and-play and co-delivery. We specifically utilize the cowpea mosaic virus (CPMV) and the virus-like particles from bacteriophage Qß as adjuvants and bind the model antigen ovalbumin (OVA). Successful binding of the antigen to the adjuvant/carrier was verified by SDS-PAGE, western blot, and ELISA. Immunization in C57BL/6J mice demonstrates that with Qß - but not CPMV - there is an improved antibody response against the target antigen using the Qß-NiNTA:His-OVA versus a simple admixture of antigen and adjuvant. Antibody isotyping also shows that formulation of the vaccines can alter T helper biases; while the Qß-NiNTA:His-OVA particle produces a balanced Th1/Th2 bias the admixture was strongly Th2. In a mouse model of B16F10-OVA, we further demonstrate improved survival and slower tumor growth in the vaccine groups compared to controls. The NiNTA:His chemistry demonstrates potential for rapid development of future generation vaccines enabling plug-and-play capabilities with effectiveness boosted by co-delivery to the same cell.


Assuntos
COVID-19 , Vacinas Virais , Animais , Camundongos , Histidina , Ácido Nitrilotriacético , Camundongos Endogâmicos C57BL , SARS-CoV-2 , Adjuvantes Imunológicos , Antígenos , Ovalbumina
17.
Int J Neuropsychopharmacol ; 26(3): 207-216, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36545813

RESUMO

BACKGROUND: Brain age is a popular brain-based biomarker that offers a powerful strategy for using neuroscience in clinical practice. We investigated the brain-predicted age difference (PAD) in patients with schizophrenia (SCZ), first-episode schizophrenia spectrum disorders (FE-SSDs), and treatment-resistant schizophrenia (TRS) using structural magnetic resonance imaging data. The association between brain-PAD and clinical parameters was also assessed. METHODS: We developed brain age prediction models for the association between 77 average structural brain measures and age in a training sample of controls (HCs) using ridge regression, support vector regression, and relevance vector regression. The trained models in the controls were applied to the test samples of the controls and 3 patient groups to obtain brain-based age estimates. The correlations were tested between the brain PAD and clinical measures in the patient groups. RESULTS: Model performance indicated that, regardless of the type of regression metric, the best model was support vector regression and the worst model was relevance vector regression for the training HCs. Accelerated brain aging was identified in patients with SCZ, FE-SSDs, and TRS compared with the HCs. A significant difference in brain PAD was observed between FE-SSDs and TRS using the ridge regression algorithm. Symptom severity, the Social and Occupational Functioning Assessment Scale, chlorpromazine equivalents, and cognitive function were correlated with the brain PAD in the patient groups. CONCLUSIONS: These findings suggest additional progressive neuronal changes in the brain after SCZ onset. Therefore, pharmacological or psychosocial interventions targeting brain health should be developed and provided during the early course of SCZ.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Esquizofrenia Resistente ao Tratamento , Encéfalo , Envelhecimento/fisiologia , Imageamento por Ressonância Magnética/métodos
18.
Mol Pharm ; 20(7): 3589-3597, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37294891

RESUMO

Plant virus nanoparticles can be used as drug carriers, imaging reagents, vaccine carriers, and immune adjuvants in the formulation of intratumoral in situ cancer vaccines. One example is the cowpea mosaic virus (CPMV), a nonenveloped virus with a bipartite positive-strand RNA genome with each RNA packaged separately into identical protein capsids. Based on differences in their densities, the components carrying RNA-1 (6 kb) denoted as the bottom (B) component or carrying RNA-2 (3.5 kb) denoted as the middle (M) component can be separated from each other and from a top (T) component, which is devoid of any RNA. Previous preclinical mouse studies and canine cancer trials used mixed populations of CPMV (containing B, M, and T components), so it is unclear whether the particle types differ in their efficacies. It is known that the CPMV RNA genome contributes to immunostimulation by activation of TLR7. To determine whether the two RNA genomes that have different sizes and unrelated sequences cause different immune stimulation, we compared the therapeutic efficacies of B and M components and unfractionated CPMV in vitro and in mouse cancer models. We found that separated B and M particles behaved similarly to the mixed CPMV, activating innate immune cells to induce the secretion of pro-inflammatory cytokines such as IFNα, IFNγ, IL-6, and IL-12, while inhibiting immunosuppressive cytokines such as TGF-ß and IL-10. In murine models of melanoma and colon cancer, the mixed and separated CPMV particles all significantly reduced tumor growth and prolonged survival with no significant difference. This shows that the specific RNA genomes similarly stimulate the immune system even though B particles have 40% more RNA than M particles; each CPMV particle type can be used as an effective adjuvant against cancer with the same efficacy as native mixed CPMV. From a translational point of view, the use of either B or M component vs the mixed CPMV formulation offers the advantage that separated B or M alone is noninfectious toward plants and thus provides agronomic safety.


Assuntos
Vacinas Anticâncer , Comovirus , Melanoma , Animais , Cães , Camundongos , Comovirus/fisiologia , RNA Viral/genética , Modelos Animais de Doenças , Citocinas , Vacinação
19.
Nature ; 549(7672): 389-393, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28854169

RESUMO

The pathophysiology of neurodegenerative diseases is poorly understood and there are few therapeutic options. Neurodegenerative diseases are characterized by progressive neuronal dysfunction and loss, and chronic glial activation. Whether microglial activation, which is generally viewed as a secondary process, is harmful or protective in neurodegeneration remains unclear. Late-onset neurodegenerative disease observed in patients with histiocytoses, which are clonal myeloid diseases associated with somatic mutations in the RAS-MEK-ERK pathway such as BRAF(V600E), suggests a possible role of somatic mutations in myeloid cells in neurodegeneration. Yet the expression of BRAF(V600E) in the haematopoietic stem cell lineage causes leukaemic and tumoural diseases but not neurodegenerative disease. Microglia belong to a lineage of adult tissue-resident myeloid cells that develop during organogenesis from yolk-sac erythro-myeloid progenitors (EMPs) distinct from haematopoietic stem cells. We therefore hypothesized that a somatic BRAF(V600E) mutation in the EMP lineage may cause neurodegeneration. Here we show that mosaic expression of BRAF(V600E) in mouse EMPs results in clonal expansion of tissue-resident macrophages and a severe late-onset neurodegenerative disorder. This is associated with accumulation of ERK-activated amoeboid microglia in mice, and is also observed in human patients with histiocytoses. In the mouse model, neurobehavioural signs, astrogliosis, deposition of amyloid precursor protein, synaptic loss and neuronal death were driven by ERK-activated microglia and were preventable by BRAF inhibition. These results identify the fetal precursors of tissue-resident macrophages as a potential cell-of-origin for histiocytoses and demonstrate that a somatic mutation in the EMP lineage in mice can drive late-onset neurodegeneration. Moreover, these data identify activation of the MAP kinase pathway in microglia as a cause of neurodegeneration and this offers opportunities for therapeutic intervention aimed at the prevention of neuronal death in neurodegenerative diseases.


Assuntos
Células Precursoras Eritroides/patologia , Sistema de Sinalização das MAP Quinases , Mutação , Células Progenitoras Mieloides/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Animais , Células Clonais/enzimologia , Células Clonais/metabolismo , Células Clonais/patologia , Modelos Animais de Doenças , Células Precursoras Eritroides/enzimologia , Células Precursoras Eritroides/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Histiocitose/enzimologia , Histiocitose/genética , Histiocitose/metabolismo , Histiocitose/patologia , Humanos , Macrófagos/enzimologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Microglia/enzimologia , Microglia/metabolismo , Microglia/patologia , Mosaicismo , Células Progenitoras Mieloides/enzimologia , Células Progenitoras Mieloides/metabolismo , Doenças Neurodegenerativas/enzimologia , Doenças Neurodegenerativas/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/metabolismo
20.
Sensors (Basel) ; 23(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36991999

RESUMO

In recent times, due to the high operating frequency and low operating voltage of modern electronic devices, intended electromagnetic interference (IEMI) has been the cause of increasing damage. In particular, targets with precision electronics such as aircrafts or missiles have shown that a high-power microwave (HPM) may cause malfunction or partial destruction of the GPS or the avionic control system. Analysis of the effects of IEMI requires electromagnetic numerical analyses. However, there are limitations to conventional numerical techniques, such as the finite element method, method of moment, or finite difference time domain method, due to the complexity and large electrical length of a real target system. In this paper, we proposed a new cylindrical mode matching (CMM) technique to analyze IEMI of the generic missile (GENEC) model, which is a hollow metal cylinder with multiple apertures. Using the CMM, we can quickly analyze the effect of the IEMI inside the GENEC model from 1.7 to 2.5 GHz. The results were compared with those of the measurements and, for verification, with the FEKO, a commercial software program developed by Altair Engineering, and showed good agreement. In this paper, the electro-optic (EO) probe was used to measure the electric field inside the GENEC model.

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