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1.
Nature ; 597(7878): 666-671, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34588666

RESUMO

The use of non-fullerene acceptors (NFAs) in organic solar cells has led to power conversion efficiencies as high as 18%1. However, organic solar cells are still less efficient than inorganic solar cells, which typically have power conversion efficiencies of more than 20%2. A key reason for this difference is that organic solar cells have low open-circuit voltages relative to their optical bandgaps3, owing to non-radiative recombination4. For organic solar cells to compete with inorganic solar cells in terms of efficiency, non-radiative loss pathways must be identified and suppressed. Here we show that in most organic solar cells that use NFAs, the majority of charge recombination under open-circuit conditions proceeds via the formation of non-emissive NFA triplet excitons; in the benchmark PM6:Y6 blend5, this fraction reaches 90%, reducing the open-circuit voltage by 60 mV. We prevent recombination via this non-radiative channel by engineering substantial hybridization between the NFA triplet excitons and the spin-triplet charge-transfer excitons. Modelling suggests that the rate of back charge transfer from spin-triplet charge-transfer excitons to molecular triplet excitons may be reduced by an order of magnitude, enabling re-dissociation of the spin-triplet charge-transfer exciton. We demonstrate NFA systems in which the formation of triplet excitons is suppressed. This work thus provides a design pathway for organic solar cells with power conversion efficiencies of 20% or more.

2.
J Immunol ; 211(3): 443-452, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37314415

RESUMO

"Adaptive" NK cells, characterized by FcRγ deficiency and enhanced responsiveness to Ab-bound, virus-infected cells, have been found in certain hCMV-seropositive individuals. Because humans are exposed to numerous microbes and environmental agents, specific relationships between hCMV and FcRγ-deficient NK cells (also known as g-NK cells) have been challenging to define. Here, we show that a subgroup of rhesus CMV (RhCMV)-seropositive macaques possesses FcRγ-deficient NK cells that stably persist and display a phenotype resembling human FcRγ-deficient NK cells. Moreover, these macaque NK cells resembled human FcRγ-deficient NK cells with respect to functional characteristics, including enhanced responsiveness to RhCMV-infected target in an Ab-dependent manner and hyporesponsiveness to tumor and cytokine stimulation. These cells were not detected in specific pathogen-free (SPF) macaques free of RhCMV and six other viruses; however, experimental infection of SPF animals with RhCMV strain UCD59, but not RhCMV strain 68-1 or SIV, led to induction of FcRγ-deficient NK cells. In non-SPF macaques, coinfection by RhCMV with other common viruses was associated with higher frequencies of FcRγ-deficient NK cells. These results support a causal role for specific CMV strain(s) in the induction of FcRγ-deficient NK cells and suggest that coinfection by other viruses further expands this memory-like NK cell pool.


Assuntos
Coinfecção , Infecções por Citomegalovirus , Viroses , Animais , Humanos , Citomegalovirus/genética , Macaca mulatta , Células Matadoras Naturais
3.
Nano Lett ; 24(4): 1153-1159, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232325

RESUMO

Twin structures possess distinct physical and chemical properties by virtue of their specific twin configuration. However, twinning and detwinning processes are not fully understood on the atomic scale. Integrating in situ high resolution transmission electron microscopy and molecular dynamic simulations, we find tensile strain in the asymmetrical 5-fold twins of Au nanoparticles leads to twin boundary migration through dislocation sliding (slipping of an atomic layer) along twin boundaries and dislocation reactions at the 5-fold axis under an electron beam. Migration of one or two layers of twin planes is governed by energy barriers, but overall, the total energy, including surface, lattice strain, and twin boundary energy, is relaxed after consecutive twin boundary migration, leading to a detwinning process. In addition, surface rearrangement of 5-fold twinned nanoparticles can aid in the detwinning process.

4.
Nano Lett ; 24(4): 1074-1080, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38236762

RESUMO

Herein, we present a synthetic approach to fabricate Au nanoheptamers composed of six individual Au nanospheres interconnected through thin metal bridges arranged in an octahedral configuration. The resulting structures envelop central Au nanospheres, producing Au nanosphere heptamers with an open architectural arrangement. Importantly, the initial Pt coating of the Au nanospheres is a crucial step for protecting the inner Au nanospheres during multiple reactions. As-synthesized Au nanoheptamers exhibit multiple hot spots formed by nanogaps between nanospheres, resulting in strong electromagnetic near-fields. Additionally, we conducted surface-enhanced Raman-scattering-based detection of a chemical warfare agent simulant in the gas phase and achieved a limit of detection of 100 ppb, which is 3 orders lower than that achieved using Au nanospheres and Au nanohexamers. This pseudocore-shell nanostructure represents a significant advancement in the realm of complex nanoparticle synthesis, moving the field one step closer to sophisticated nanoparticle engineering.

5.
Am J Transplant ; 24(2): 222-238, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37321453

RESUMO

Pure laparoscopic donor hepatectomy (PLDH) has become a routine procedure at Seoul National University Hospital, and the pure laparoscopic method is now being applied to liver recipients as well. This study aimed to review the procedure and outcomes of PLDH to identify any areas that required improvement. Data from 556 donors who underwent PLDH between November 2015 and December 2021 and their recipients were retrospectively reviewed. Among these, 541 patients underwent pure laparoscopic donor right hepatectomy (PLDRH). The mean hospital stay of the donor was 7.2 days, and the rate of grade I, II, IIIa, and IIIb complications was 2.2%, 2.7%, 1.3%, and 0.9%, respectively, without any irreversible disabilities or mortalities. The most common early and late major complications in the recipient were intraabdominal bleeding (n = 47, 8.5%) and biliary problems (n = 198, 35.6%), respectively. Analysis of the PLDRH procedure showed that operative time, liver removal time, warm ischemic time, Δhemoglobin%, Δtotal bilirubin%, and postoperative hospital stay decreased significantly as the number of cases accumulated. In conclusion, the operative outcomes of PLDRH improved as the number of cases increased. However, continuous caution is needed because major complications still occur in donors and recipients even after hundreds of cases.


Assuntos
Laparoscopia , Transplante de Fígado , Humanos , Hepatectomia/métodos , Seul , Estudos Retrospectivos , Transplante de Fígado/efeitos adversos , Doadores Vivos , Fígado/cirurgia , Coleta de Tecidos e Órgãos/efeitos adversos , Laparoscopia/métodos , Duração da Cirurgia , Hospitais , Complicações Pós-Operatórias/etiologia
6.
Ann Surg ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38887930

RESUMO

OBJECTIVE: To assess the utility of tumor-intrinsic and cancer-associated fibroblast (CAF) subtypes of pancreatic ductal adenocarcinoma (PDAC) in predicting response to neoadjuvant therapy (NAT) and overall survival. BACKGROUND: PDAC remains a deadly disease with limited treatment options, and both the tumor as well as the microenvironment play an important role in pathogenesis. Gene expression-based tumor-intrinsic subtypes (classical and basal-like) have been shown to predict outcomes, but tumor microenvironment subtypes are still evolving. METHODS: RNA-sequencing was performed on 114 deidentified resected PDAC tumors. Clinical data were collected by retrospective chart review. Single sample classifiers (SSCs) were used to determine classical and basal-like subtypes as well as tumor-permissive permCAF and tumor-restraining restCAF subtypes. Survival was analyzed using log-rank test. RESULTS: Patients who received NAT had an increase in overall survival (OS), with median survival of 27.9 months compared to 20.1 months for those who did not receive NAT, but the difference did not reach statistical significance (HR 0.64, P=0.076). Either tumor-intrinsic or CAF subtypes alone were associated with OS regardless of NAT or no NAT, and patients with classical or restCAF subtype had the best outcomes. When evaluated together, patients with classical-restCAF subtype had the best OS and basal-permCAF the worst OS (P<0.0001). NAT patients with classical-restCAF subtype demonstrated the longest OS compared to the other groups (P=0.00041). CONCLUSIONS: CAF subtypes have an additive effect over tumor-intrinsic subtypes in predicting survival with or without neoadjuvant FOLFIRINOX in PDAC. Molecular subtyping of both tumor and CAF compartments of PDAC may be important steps in selecting first-line systemic therapy.

7.
Bioinformatics ; 39(12)2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995286

RESUMO

MOTIVATION: Predicting protein structures with high accuracy is a critical challenge for the broad community of life sciences and industry. Despite progress made by deep neural networks like AlphaFold2, there is a need for further improvements in the quality of detailed structures, such as side-chains, along with protein backbone structures. RESULTS: Building upon the successes of AlphaFold2, the modifications we made include changing the losses of side-chain torsion angles and frame aligned point error, adding loss functions for side chain confidence and secondary structure prediction, and replacing template feature generation with a new alignment method based on conditional random fields. We also performed re-optimization by conformational space annealing using a molecular mechanics energy function which integrates the potential energies obtained from distogram and side-chain prediction. In the CASP15 blind test for single protein and domain modeling (109 domains), DeepFold ranked fourth among 132 groups with improvements in the details of the structure in terms of backbone, side-chain, and Molprobity. In terms of protein backbone accuracy, DeepFold achieved a median GDT-TS score of 88.64 compared with 85.88 of AlphaFold2. For TBM-easy/hard targets, DeepFold ranked at the top based on Z-scores for GDT-TS. This shows its practical value to the structural biology community, which demands highly accurate structures. In addition, a thorough analysis of 55 domains from 39 targets with publicly available structures indicates that DeepFold shows superior side-chain accuracy and Molprobity scores among the top-performing groups. AVAILABILITY AND IMPLEMENTATION: DeepFold tools are open-source software available at https://github.com/newtonjoo/deepfold.


Assuntos
Proteínas , Software , Conformação Proteica , Proteínas/química , Estrutura Secundária de Proteína , Dobramento de Proteína
8.
Immunity ; 42(3): 431-42, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25786175

RESUMO

Long-lived "memory-like" NK cells have been identified in individuals infected by human cytomegalovirus (HCMV), but little is known about how the memory-like NK cell pool is formed. Here, we have shown that HCMV-infected individuals have several distinct subsets of memory-like NK cells that are often deficient for multiple transcription factors and signaling proteins, including tyrosine kinase SYK, for which the reduced expression was stable over time and correlated with epigenetic modification of the gene promoter. Deficient expression of these proteins was largely confined to the recently discovered FcRγ-deficient NK cells that display enhanced antibody-dependent functional activity. Importantly, FcRγ-deficient NK cells exhibited robust preferential expansion in response to virus-infected cells (both HCMV and influenza) in an antibody-dependent manner. These findings suggest that the memory-like NK cell pool is shaped and maintained by a mechanism that involves both epigenetic modification of gene expression and antibody-dependent expansion.


Assuntos
Anticorpos/imunologia , Infecções por Citomegalovirus/genética , Epigênese Genética/imunologia , Memória Imunológica , Células Matadoras Naturais/imunologia , Proliferação de Células , Citomegalovirus/imunologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/virologia , Metilação de DNA , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Perfilação da Expressão Gênica , Humanos , Imunofenotipagem , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Células Matadoras Naturais/classificação , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Análise em Microsséries , Subfamília C de Receptores Semelhantes a Lectina de Células NK/deficiência , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Regiões Promotoras Genéticas , Proteínas Tirosina Quinases/deficiência , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/imunologia , Receptores de IgG/deficiência , Receptores de IgG/genética , Receptores de IgG/imunologia , Transdução de Sinais , Quinase Syk
9.
BMC Public Health ; 24(1): 1412, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802817

RESUMO

BACKGROUND: Parental depression is a significant problem that negatively affects parents' welfare and influences family dynamics, children's academic and health behaviors, and mental health. However, there is limited evidence regarding the impact of the parental depression into the children's' psychological and physical wellbeing on Asian cultures. This study examined the psychological burdens and health behaviors of adolescent children with parents with depression in the Republic of Korea. METHODS: We conducted a cross-sectional study using data from the Korean National Health and Nutrition Examination Survey (KNHANES) spanning 2013 to 2021 to compare health behaviors and mental health outcomes between 203 adolescent children with parents diagnosed with depression and 3,856 control adolescents aged 12-19 years. RESULTS: Following multivariate adjustments, the risk of depressive mood for more than two weeks was significantly increased in boys with parental depression (adjusted Odds Ratio [aOR] = 2.05, 95% Confidence Interval [CI] = 1.91-3.52) and adolescents with parents with moderate-to-severe depression (aOR = 2.60, 95% CI = 1.17-5.77). Adolescents with parental depression reported significantly worse subjective health status (aOR = 1.88, 95% CI = 1.05-3.36) and higher stress levels (aOR = 1.91, 95% CI = 1.33-2.76). Additionally, when parental depression was present and the time since depression diagnosis was more than five years, adolescents with parental depression exhibited even poorer subjective health status and higher stress levels. CONCLUSIONS: The study found that adolescents whose parents experienced depression had poorer mental health than those whose parents did not have mental health issues. These findings emphasize the importance of providing support for the mental health of adolescents in families affected by parental depression.


Assuntos
Depressão , Comportamentos Relacionados com a Saúde , Humanos , Adolescente , Masculino , Feminino , Estudos Transversais , República da Coreia/epidemiologia , Depressão/epidemiologia , Depressão/psicologia , Criança , Adulto Jovem , Filho de Pais com Deficiência/psicologia , Filho de Pais com Deficiência/estatística & dados numéricos , Pais/psicologia , Inquéritos Nutricionais , Saúde Mental , Bem-Estar Psicológico
10.
Nano Lett ; 23(4): 1546-1554, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36757958

RESUMO

For the colloidal nanophotonic structures, a transmission electron microscope (TEM) grid has been widely used as a substrate of dark-field microscopy because a nanometer-scale feature can be effectively determined by TEM imaging following dark-field microscopic studies. However, an optically lossy carbon layer has been implemented in conventional TEM grids. A broadband scattering from the edges of the TEM grid further restricted an accessible signal-to-noise ratio. Herein, we demonstrate that the freely suspended, ultrathin, and wide-scale transparent nanomembrane can address such challenges. We developed a 1 mm by 600 µm scale and 20 nm thick poly(vinyl formal) nanomembrane, whose area is around 180 times wider than a conventional TEM grid, so that the possible broadband scattering at the edges of the grid was effectively excluded. Also, such nanomembranes can be formed without the assistance of carbon support; allowing us to achieve the highest signal-to-background ratio of scattering among other substrates.

11.
N Engl J Med ; 382(2): 111-119, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31733181

RESUMO

BACKGROUND: The timing and indications for surgical intervention in asymptomatic patients with severe aortic stenosis remain controversial. METHODS: In a multicenter trial, we randomly assigned 145 asymptomatic patients with very severe aortic stenosis (defined as an aortic-valve area of ≤0.75 cm2 with either an aortic jet velocity of ≥4.5 m per second or a mean transaortic gradient of ≥50 mm Hg) to early surgery or to conservative care according to the recommendations of current guidelines. The primary end point was a composite of death during or within 30 days after surgery (often called operative mortality) or death from cardiovascular causes during the entire follow-up period. The major secondary end point was death from any cause during follow-up. RESULTS: In the early-surgery group, 69 of 73 patients (95%) underwent surgery within 2 months after randomization, and there was no operative mortality. In an intention-to-treat analysis, a primary end-point event occurred in 1 patient in the early-surgery group (1%) and in 11 of 72 patients in the conservative-care group (15%) (hazard ratio, 0.09; 95% confidence interval [CI], 0.01 to 0.67; P = 0.003). Death from any cause occurred in 5 patients in the early-surgery group (7%) and in 15 patients in the conservative-care group (21%) (hazard ratio, 0.33; 95% CI, 0.12 to 0.90). In the conservative-care group, the cumulative incidence of sudden death was 4% at 4 years and 14% at 8 years. CONCLUSIONS: Among asymptomatic patients with very severe aortic stenosis, the incidence of the composite of operative mortality or death from cardiovascular causes during the follow-up period was significantly lower among those who underwent early aortic-valve replacement surgery than among those who received conservative care. (Funded by the Korean Institute of Medicine; RECOVERY ClinicalTrials.gov number, NCT01161732.).


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Tratamento Conservador , Idoso , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/terapia , Doenças Assintomáticas/terapia , Doenças Cardiovasculares/mortalidade , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Complicações Pós-Operatórias/mortalidade
12.
Gastroenterology ; 162(7): 2018-2031, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35216965

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) has a hypoxic, immunosuppressive stroma that contributes to its resistance to immune checkpoint blockade therapies. The hypoxia-inducible factors (HIFs) mediate the cellular response to hypoxia, but their role within the PDAC tumor microenvironment remains unknown. METHODS: We used a dual recombinase mouse model to delete Hif1α or Hif2α in α-smooth muscle actin-expressing cancer-associated fibroblasts (CAFs) arising within spontaneous pancreatic tumors. The effects of CAF HIF2α expression on tumor progression and composition of the tumor microenvironment were evaluated by Kaplan-Meier analysis, reverse transcription quantitative real-time polymerase chain reaction, histology, immunostaining, and by both bulk and single-cell RNA sequencing. CAF-macrophage crosstalk was modeled ex vivo using conditioned media from CAFs after treatment with hypoxia and PT2399, an HIF2 inhibitor currently in clinical trials. Syngeneic flank and orthotopic PDAC models were used to assess whether HIF2 inhibition improves response to immune checkpoint blockade. RESULTS: CAF-specific deletion of Hif2α, but not Hif1α, suppressed PDAC tumor progression and growth, and improved survival of mice by 50% (n = 21-23 mice/group, Log-rank P = .0009). Deletion of CAF-HIF2 modestly reduced tumor fibrosis and significantly decreased the intratumoral recruitment of immunosuppressive M2 macrophages and regulatory T cells. Treatment with the clinical HIF2 inhibitor PT2399 significantly reduced in vitro macrophage chemotaxis and M2 polarization, and improved tumor responses to immunotherapy in both syngeneic PDAC mouse models. CONCLUSIONS: Together, these data suggest that stromal HIF2 is an essential component of PDAC pathobiology and is a druggable therapeutic target that could relieve tumor microenvironment immunosuppression and enhance immune responses in this disease.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/patologia , Humanos , Hipóxia/metabolismo , Inibidores de Checkpoint Imunológico , Terapia de Imunossupressão , Camundongos , Neoplasias Pancreáticas/patologia , Microambiente Tumoral , Neoplasias Pancreáticas
13.
Anal Chem ; 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633590

RESUMO

An exquisite, versatile, and reproducible quantification of DNA loading on gold nanoparticles (Au NPs) has long been pursued because this loading influences the analytical, therapeutic, and self-assembly behaviors of DNA-Au NPs. Nevertheless, the existing methods used thus far rely solely on the invasive detachment and subsequent spectroscopic quantification of DNA, which are error-prone and highly dependent on trained personnel. Here, we present a non-invasive optical framework that can determine the number of DNA strands on Au NPs by versatile one-step measurement of the visible absorption spectra of DNA-Au NP solutions without any invasive modifications or downstream processes. Using effective medium theory in conjunction with electromagnetic numerical calculation, the change in DNA loading density, resulting from varying the ion concentration, Au NP size, DNA strand length, and surrounding temperature, can be tracked in situ merely by the one-step measurement of visible absorption spectra, which is otherwise impossible to achieve. Moreover, the simplicity and robustness of this method promote reproducible DNA loading quantification regardless of experimental adeptness, which is in stark contrast with existing invasive and multistep methods. Overall, the optical framework outlined in this work can contribute to democratizing research on DNA-Au NPs and facilitating their rapid adoption in transformative applications.

14.
Small ; 19(17): e2206377, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36617524

RESUMO

Here, the rational design of complex PtAu double nanoframes (DNFs) for plasmon-enhanced electrocatalytic activity toward the methanol oxidation reaction (MOR) is reported. The synthetic strategy for the DNFs consists of on-demand multiple synthetic chemical toolkits, including well-faceted Au growth, rim-on selective Pt deposition, and selective Au etching steps. DNFs are synthesized by utilizing Au truncated octahedrons (TOh) as a starting template. The outer octahedral (Oh) nanoframes (NFs) nest the inner TOh NFs, eventually forming DNFs with a tunable intra-nanogap distance. Residual Au adatoms on Pt skeletons act as light entrappers and produce plasmonic hot spots between inner and outer frames through localized surface plasmon resonance (LSPR) coupling, which promotes enhanced electrocatalytic activity for the MOR. Importantly, the correlation between the gap-induced hot carriers and electrocatalytic activity is evaluated. The highest catalytic activity is achieved when the gap is the narrowest. To further harness their light-trapping capability, hierarchically structured triple NFs (TNFs) are synthesized, wherein three NFs are entangled in a single entity with a high density of hot regions, exhibiting superior electrocatalytic activity toward the MOR with a sixfold larger current density under light irradiation compared to the dark conditions.

15.
Am J Pathol ; 192(1): 72-86, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619134

RESUMO

Chronic gut inflammation such as inflammatory bowel disease is believed to be associated with neurodegenerative diseases in humans. However, the direct evidence for and the underlying mechanism of this brain-gut interaction remain elusive. In this study, manganese-enhanced magnetic resonance imaging was used to assess functional brain activity from awake and freely moving mice with chronic colitis. Manganese ion uptake (indicative of Ca2+ influx into neuronal cells) and accumulation were reduced in the hippocampus of chronic colitis mice compared with control mice. Long-term memory declined and neuroinflammatory signals, including IL-1ß production and activation of caspase-1, caspase-11, and gasdermin, were induced. High-mobility group box 1 (HMGB1) levels were elevated both in the serum and in the hippocampus; however, lipopolysaccharide (LPS) levels remained at low levels without significant changes in these samples. The blood-brain barrier permeability was increased in chronic colitis mice. In the presence of LPS, HMGB1 treatment induced the activation of caspase-11 and gasdermin in the mouse microglial cell line SIM-A9. These findings suggest that HMGB1 released from the inflamed intestine may move to the brain through the blood circulatory system; in conjunction with a low level of endogenous LPS, elevated HMGB1 can subsequently activate caspase-mediated inflammatory responses in the brain.


Assuntos
Encéfalo/patologia , Inflamação/patologia , Intestinos/patologia , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Barreira Hematoencefálica/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Caspases/metabolismo , Linhagem Celular , Doença Crônica , Colite/sangue , Colite/patologia , Citocinas/metabolismo , Proteína HMGB1/metabolismo , Hipocampo/enzimologia , Hipocampo/patologia , Inflamação/sangue , Inflamação/diagnóstico por imagem , Inflamação/fisiopatologia , Lipopolissacarídeos , Imageamento por Ressonância Magnética , Memória de Longo Prazo , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Permeabilidade , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Piroptose
16.
Nucleic Acids Res ; 49(11): 6596-6603, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110422

RESUMO

DNA origami requires long scaffold DNA to be aligned with the guidance of short staple DNA strands. Scaffold DNA is produced in Escherichia coli as a form of the M13 bacteriophage by rolling circle amplification (RCA). This study shows that RCA can be reconfigured by reducing phage protein V (pV) expression, improving the production throughput of scaffold DNA by at least 5.66-fold. The change in pV expression was executed by modifying the untranslated region sequence and monitored using a reporter green fluorescence protein fused to pV. In a separate experiment, pV expression was controlled by an inducer. In both experiments, reduced pV expression was correlated with improved M13 bacteriophage production. High-cell-density cultivation was attempted for mass scaffold DNA production, and the produced scaffold DNA was successfully folded into a barrel shape without compromising structural quality. This result suggested that scaffold DNA production throughput can be significantly improved by reprogramming the RCA in E. coli.


Assuntos
Bacteriófago M13/fisiologia , DNA de Cadeia Simples/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas Virais/genética , Regiões 5' não Traduzidas , Bacteriófago M13/genética , Bacteriófago M13/metabolismo , DNA de Cadeia Simples/ultraestrutura , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Mutação , Proteínas Virais/metabolismo , Replicação Viral
17.
Sensors (Basel) ; 23(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36991829

RESUMO

Memristors mimic synaptic functions in advanced electronics and image sensors, thereby enabling brain-inspired neuromorphic computing to overcome the limitations of the von Neumann architecture. As computing operations based on von Neumann hardware rely on continuous memory transport between processing units and memory, fundamental limitations arise in terms of power consumption and integration density. In biological synapses, chemical stimulation induces information transfer from the pre- to the post-neuron. The memristor operates as resistive random-access memory (RRAM) and is incorporated into the hardware for neuromorphic computing. Hardware composed of synaptic memristor arrays is expected to lead to further breakthroughs owing to their biomimetic in-memory processing capabilities, low power consumption, and amenability to integration; these aspects satisfy the upcoming demands of artificial intelligence for higher computational loads. Among the tremendous efforts toward achieving human-brain-like electronics, layered 2D materials have demonstrated significant potential owing to their outstanding electronic and physical properties, facile integration with other materials, and low-power computing. This review discusses the memristive characteristics of various 2D materials (heterostructures, defect-engineered materials, and alloy materials) used in neuromorphic computing for image segregation or pattern recognition. Neuromorphic computing, the most powerful artificial networks for complicated image processing and recognition, represent a breakthrough in artificial intelligence owing to their enhanced performance and lower power consumption compared with von Neumann architectures. A hardware-implemented CNN with weight control based on synaptic memristor arrays is expected to be a promising candidate for future electronics in society, offering a solution based on non-von Neumann hardware. This emerging paradigm changes the computing algorithm using entirely hardware-connected edge computing and deep neural networks.

18.
Nano Lett ; 22(4): 1734-1740, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138110

RESUMO

The development of a stepwise synthetic strategy for Au ring-in-a-triangle nanoframes with a high degree of structural solidity is essential to the advancement of highly amplified near-field focusing. This strategy leads to the formation of an inscribed nanoring in a triangular metal frame with stability to withstand elevated temperatures and an oxidizing environment, which is critical for successful single-particle surface-enhanced Raman scattering (SERS). The existence of inscribed nanorings plays an important role in enhancing the so-called "lightning rod effect," whereby the electromagnetic near-field enhancement occurs on the highly curved curvature of a metallic interface. We evaluated the corresponding single-particle SERS as a function of the thickness of the rims and then constructed two-dimensional (2D) bulk SERS substrates, wherein an ensemble of hotspots exists. The synergic contribution from both inter- and intrahotspots allowed the outstanding linearity of the calibration curve and the lowest limit of detection, ∼10-18 M for the analyte concentration.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos
19.
Int J Mol Sci ; 24(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37108390

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease which causes breathing problems. YPL-001, consisting of six iridoids, has potent inhibitory efficacy against COPD. Although YPL-001 has completed clinical trial phase 2a as a natural drug for COPD treatment, the most effective iridoid in YPL-001 and its mechanism for reducing airway inflammation remain unclear. To find an iridoid most effectively reducing airway inflammation, we examined the inhibitory effects of the six iridoids in YPL-001 on TNF or PMA-stimulated inflammation (IL-6, IL-8, or MUC5AC) in NCI-H292 cells. Here, we show that verproside among the six iridoids most strongly suppresses inflammation. Both TNF/NF-κB-induced MUC5AC expression and PMA/PKCδ/EGR-1-induced IL-6/-8 expression are successfully reduced by verproside. Verproside also shows anti-inflammatory effects on a broad range of airway stimulants in NCI-H292 cells. The inhibitory effect of verproside on the phosphorylation of PKC enzymes is specific to PKCδ. Finally, in vivo assay using the COPD-mouse model shows that verproside effectively reduces lung inflammation by suppressing PKCδ activation and mucus overproduction. Altogether, we propose YPL-001 and verproside as candidate drugs for treating inflammatory lung diseases that act by inhibiting PKCδ activation and its downstream pathways.


Assuntos
Interleucina-6 , Doença Pulmonar Obstrutiva Crônica , Animais , Humanos , Camundongos , Células Epiteliais/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-6/metabolismo , Iridoides/farmacologia , Iridoides/uso terapêutico , Iridoides/metabolismo , Pulmão/metabolismo , NF-kappa B/metabolismo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Proteína Quinase C-delta/metabolismo
20.
Int J Mol Sci ; 24(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37569348

RESUMO

Asthma is a chronic inflammatory lung disease that causes respiratory difficulties. Black ginseng extract (BGE) has preventative effects on respiratory inflammatory diseases such as asthma. However, the pharmacological mechanisms behind the anti-asthmatic activity of BGE remain unknown. To investigate the anti-asthmatic mechanism of BGE, phorbol 12-myristate 13-acetate plus ionomycin (PMA/Iono)-stimulated mouse EL4 cells and ovalbumin (OVA)-induced mice with allergic airway inflammation were used. Immune cells (eosinophils/macrophages), interleukin (IL)-4, -5, -13, and serum immunoglobulin E (IgE) levels were measured using an enzyme-linked immunosorbent assay. Inflammatory cell recruitment and mucus secretion in the lung tissue were estimated. Protein expression was analyzed via Western blotting, including that of inducible nitric oxide synthase (iNOS) and the activation of protein kinase C theta (PKCθ) and its downstream signaling molecules. BGE decreased T helper (Th)2 cytokines, serum IgE, mucus secretion, and iNOS expression in mice with allergic airway inflammation, thereby providing a protective effect. Moreover, BGE and its major ginsenosides inhibited the production of Th2 cytokines in PMA/Iono-stimulated EL4 cells. In EL4 cells, these outcomes were accompanied by the inactivation of PKCθ and its downstream transcription factors, such as nuclear factor of activated T cells (NFAT), nuclear factor kappa B (NF-κB), activator of transcription 6 (STAT6), and GATA binding protein 3 (GATA3), which are involved in allergic airway inflammation. BGE also inhibited the activation of PKCθ and the abovementioned transcriptional factors in the lung tissue of mice with allergic airway inflammation. These results highlight the potential of BGE as a useful therapeutic and preventative agent for allergic airway inflammatory diseases such as allergic asthma.


Assuntos
Antiasmáticos , Asma , Hipersensibilidade , Panax , Animais , Camundongos , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Interleucina-4/metabolismo , Asma/metabolismo , Pulmão/metabolismo , Citocinas/metabolismo , Hipersensibilidade/metabolismo , Transdução de Sinais , Inflamação/metabolismo , Imunoglobulina E , Panax/metabolismo , Ovalbumina , Camundongos Endogâmicos BALB C , Modelos Animais de Doenças
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