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1.
J Med Virol ; 96(4): e29600, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38591240

RESUMO

The lower respiratory system serves as the target and barrier for beta-coronavirus (beta-CoV) infections. In this study, we explored beta-CoV infection dynamics in human bronchial epithelial (HBE) organoids, focusing on HCoV-OC43, SARS-CoV, MERS-CoV, and SARS-CoV-2. Utilizing advanced organoid culture techniques, we observed robust replication for all beta-CoVs, particularly noting that SARS-CoV-2 reached peak viral RNA levels at 72 h postinfection. Through comprehensive transcriptomic analysis, we identified significant shifts in cell population dynamics, marked by an increase in goblet cells and a concurrent decrease in ciliated cells. Furthermore, our cell tropism analysis unveiled distinct preferences in viral targeting: HCoV-OC43 predominantly infected club cells, while SARS-CoV had a dual tropism for goblet and ciliated cells. In contrast, SARS-CoV-2 primarily infected ciliated cells, and MERS-CoV showed a marked affinity for goblet cells. Host factor analysis revealed the upregulation of genes encoding viral receptors and proteases. Notably, HCoV-OC43 induced the unfolded protein response pathway, which may facilitate viral replication. Our study also reveals a complex interplay between inflammatory pathways and the suppression of interferon responses during beta-CoV infections. These findings provide insights into host-virus interactions and antiviral defense mechanisms, contributing to our understanding of beta-CoV infections in the respiratory tract.


Assuntos
Coronavirus Humano OC43 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Linhagem Celular , Brônquios , SARS-CoV-2 , Interferons , Organoides
2.
EXCLI J ; 23: 130-142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487085

RESUMO

Resistance band training (RBT) with functional electrical stimulation (FES) may be an effective exercise regimen for improving age-related motor impairments. This preliminary study investigated the potential effects of bimanual RBT with FES on upper limb motor functions in older adults. This study randomly assigned 22 elderly people to the bimanual RBT with FES (Bi-RBT+FES) group and the RBT without FES (Bi-RBT) group. All participants performed isometric hand-grip force control tasks in unimanual (dominant and non-dominant) and bimanual conditions before and after four weeks of exercise for each group. We quantified the mean force, force accuracy, force variability, and force regularity at two targeted force levels (i.e., 10 % and 40 % of maximum voluntary contraction; MVC) to estimate changes in force control capabilities. The results revealed that the Bi-RBT+FES group demonstrated a greater force accuracy in the dominant hand at 10 % of MVC after training. Non-dominant hands in the Bi-RBT+FES group increased force accuracy at 40 % of MVC and reduced force variability collapsed across two targeted force levels. Both groups showed a decrease in force regularity after training. These preliminary results indicate that Bi-RBT+FES may be a viable option to facilitate functional recovery of the upper limbs in older adults.

3.
AAPS J ; 25(5): 81, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37589795

RESUMO

mRNA vaccines can be translated into protein antigens, in vivo, to effectively induce humoral and cellular immunity against these proteins. While current mRNA vaccines have generated potent immune responses, the need for ultracold storage conditions (- 80 °C) and healthcare professionals to administer the vaccine through the parenteral route has somewhat limited their distribution in rural areas and developing countries. Overcoming these challenges stands to transform future deployment of mRNA vaccines. In this study, we developed an mRNA vaccine that can trigger a systemic immune response through administration via the gastrointestinal (GI) tract and is stable at 4 °C. A library of cationic branched poly(ß-amino ester) (PBAE) polymers was synthesized and characterized, from which a polymer with high intracellular mRNA delivery efficiency and immune stimulation capacity was down-selected. mRNA vaccines made with the lead polymer-elicited cellular and humoral immunity in mice. Furthermore, lyophilization conditions of the formulation were optimized to enable storage under refrigeration. Our results suggest that PBAE nanoparticles are potent mRNA delivery platforms that can elicit B cell and T cell activation, including antigen-specific cellular and humoral responses. This system can serve as an easily administrable, potent oral mRNA vaccine.


Assuntos
Nanopartículas , Vacinas Sintéticas , Animais , Camundongos , Vacinas de mRNA , Linfócitos B
4.
Cells ; 12(5)2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36899958

RESUMO

Biogenic amines are cellular components produced by the decarboxylation of amino acids; however, excessive biogenic amine production causes adverse health problems. The relationship between hepatic damage and biogenic amine levels in nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, mice were fed a high-fat diet (HFD) for 10 weeks to induce obesity, presenting early-stage of NAFLD. We administered histamine (20 mg/kg) + tyramine (100 mg/kg) via oral gavage for 6 days to mice with HFD-induced early-stage NAFLD. The results showed that combined histamine and tyramine administration increased cleaved PARP-1 and IL-1ß in the liver, as well as MAO-A, total MAO, CRP, and AST/ALT levels. In contrast, the survival rate decreased in HFD-induced NAFLD mice. Treatment with manufactured or traditional fermented soybean paste decreased biogenically elevated hepatic cleaved PARP-1 and IL-1ß expression and blood plasma MAO-A, CRP, and AST/ALT levels in HFD-induced NAFLD mice. Additionally, the biogenic amine-induced reduction in survival rate was alleviated by fermented soybean paste in HFD-induced NAFLD mice. These results show that biogenic amine-induced liver damage can be exacerbated by obesity and may adversely affect life conservation. However, fermented soybean paste can reduce biogenic amine-induced liver damage in NAFLD mice. These results suggest a beneficial effect of fermented soybean paste on biogenic amine-induced liver damage and provide a new research perspective on the relationship between biogenic amines and obesity.


Assuntos
Alimentos Fermentados , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Histamina , Camundongos Obesos , Glycine max/química , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Aminas Biogênicas , Obesidade , Monoaminoxidase , Tiramina/uso terapêutico
5.
Biomaterials ; 288: 121703, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36030104

RESUMO

Intravesical instillation is an efficient drug delivery route for the local treatment of various urological conditions. Nevertheless, intravesical instillation is associated with several challenges, including pain, urological infection, and frequent clinic visits for catheterization; these difficulties support the need for a simple and easy intravesical drug delivery platform. Here, we propose a novel biodegradable intravesical device capable of long-term, local drug delivery without a retrieval procedure. The intravesical device is composed of drug encapsulating biodegradable polycaprolactone (PCL) microcapsules and connected by a bioabsorbable Polydioxanone (PDS) suture with NdFeB magnets in the end. The device is easily inserted into the bladder and forms a 'ring' shape optimized for maximal mechanical stability as informed by finite element analysis. In this study, inserted devices were retained in a swine model for 4 weeks. Using this device, we evaluated the system's capacity for delivery of lidocaine and resiquimod and demonstrated prolonged drug release. Moreover, a cost-effectiveness analysis supports device implementation compared to the standard of care. Our data support that this device can be a versatile drug delivery platform for urologic medications.


Assuntos
Sistemas de Liberação de Medicamentos , Bexiga Urinária , Administração Intravesical , Animais , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Suínos , Bexiga Urinária/metabolismo
6.
Sci Transl Med ; 14(651): eabl4135, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35767653

RESUMO

Carbon monoxide (CO) has long been considered a toxic gas but is now a recognized bioactive gasotransmitter with potent immunomodulatory effects. Although inhaled CO is currently under investigation for use in patients with lung disease, this mode of administration can present clinical challenges. The capacity to deliver CO directly and safely to the gastrointestinal (GI) tract could transform the management of diseases affecting the GI mucosa such as inflammatory bowel disease or radiation injury. To address this unmet need, inspired by molecular gastronomy techniques, we have developed a family of gas-entrapping materials (GEMs) for delivery of CO to the GI tract. We show highly tunable and potent delivery of CO, achieving clinically relevant CO concentrations in vivo in rodent and swine models. To support the potential range of applications of foam GEMs, we evaluated the system in three distinct disease models. We show that a GEM containing CO dose-dependently reduced acetaminophen-induced hepatocellular injury, dampened colitis-associated inflammation and oxidative tissue injury, and mitigated radiation-induced gut epithelial damage in rodents. Collectively, foam GEMs have potential paradigm-shifting implications for the safe therapeutic use of CO across a range of indications.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Monóxido de Carbono/uso terapêutico , Colite/tratamento farmacológico , Gases , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Suínos
7.
Life Sci Alliance ; 5(5)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35169043

RESUMO

FTO and ALKBH5 are the two enzymes responsible for mRNA demethylation. Hence, the functional study of FTO has been focused on its mechanistic role in dynamic mRNA modification, and how this post-transcriptional regulation modulates signaling pathways. Here, we report that the functional landscape of FTO is largely associated with WNT signaling pathways but in a manner that is independent of its enzymatic activity. Re-analyses of public datasets identified the bifurcation of canonical and noncanonical WNT pathways as the major role of FTO. In FTO-depleted cells, we find that the canonical WNT/ß-Catenin signaling is attenuated in a non-cell autonomous manner via the up-regulation of DKK1. Simultaneously, this up-regulation of DKK1 promotes cell migration via activating the noncanonical WNT/PCP pathway. Unexpectedly, this regulation of DKK1 is independent of its RNA methylation status but operates at the transcriptional level, revealing a noncanonical function of FTO in gene regulation. In conclusion, this study places the functional context of FTO at the branch point of multiple WNT signaling pathways and extends its mechanistic role in gene regulation.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Via de Sinalização Wnt/fisiologia , Adenosina/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Movimento Celular , Proliferação de Células , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metilação , RNA Mensageiro/genética , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
8.
Sci Adv ; 7(48): eabj4624, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34826238

RESUMO

Diurnal variation in enzymes, hormones, and other biological mediators has long been recognized in mammalian physiology. Developments in pharmacobiology over the past few decades have shown that timing drug delivery can enhance drug efficacy. Here, we report the development of a battery-free, refillable, subcutaneous, and trocar-compatible implantable system that facilitates chronotherapy by enabling tight control over the timing of drug administration in response to external mechanical actuation. The external wearable system is coupled to a mobile app to facilitate control over dosing time. Using this system, we show the efficacy of bromocriptine on glycemic control in a diabetic rat model. We also demonstrate that antihypertensives can be delivered through this device, which could have clinical applications given the recognized diurnal variation of hypertension-related complications. We anticipate that implants capable of chronotherapy will have a substantial impact on our capacity to enhance treatment effectiveness for a broad range of chronic conditions.

9.
Mol Cell Biol ; 41(8): e0010421, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-33972392

RESUMO

N6-Methyladenosine (m6A) is the most prevalent internal RNA modification and has a widespread impact on mRNA stability and translation. Methyltransferase-like 3 (Mettl3) is a methyltransferase responsible for RNA m6A modification, and it is essential for early embryogenesis before or during gastrulation in mice and zebrafish. However, due to the early embryonic lethality, loss-of-function phenotypes of Mettl3 beyond gastrulation, especially during neurulation stages when spatial neural patterning takes place, remain elusive. Here, we address multiple roles of Mettl3 during Xenopus neurulation in anteroposterior neural patterning, neural crest specification, and neuronal cell differentiation. Knockdown of Mettl3 causes anteriorization of neurulae and tailbud embryos along with the loss of neural crest and neuronal cells. Knockdown of the m6A reader Ythdf1 and mRNA degradation factors, such as 3' to 5' exonuclease complex component Lsm1 or mRNA uridylation enzyme Tut7, also show similar neural patterning defects, suggesting that m6A-dependent mRNA destabilization regulates spatial neural patterning in Xenopus. We also address that canonical WNT signaling is inhibited in Mettl3 morphants, which may underlie the neural patterning defects of the morphants. Altogether, this study reveals functions of Mettl3 during spatial neural patterning in Xenopus.


Assuntos
Regulação da Expressão Gênica/fisiologia , Metiltransferases/metabolismo , Nucleotidiltransferases/metabolismo , RNA/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo , Animais , Linhagem Celular Tumoral , Metiltransferases/genética , Nucleotidiltransferases/genética , Estabilidade de RNA/fisiologia , Via de Sinalização Wnt/genética , Proteínas de Xenopus/genética , Xenopus laevis/genética , Peixe-Zebra/metabolismo
10.
Dev Cell ; 56(8): 1118-1130.e6, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33761320

RESUMO

Adenosine N6-methylation (m6A) is one of the most pervasive mRNA modifications, and yet the physiological significance of m6A removal (demethylation) remains elusive. Here, we report that the m6A demethylase FTO functions as a conserved regulator of motile ciliogenesis. Mechanistically, FTO demethylates and thereby stabilizes the mRNA that encodes the master ciliary transcription factor FOXJ1. Depletion of Fto in Xenopus laevis embryos caused widespread motile cilia defects, and Foxj1 was identified as one of the major phenocritical targets. In primary human airway epithelium, FTO depletion also led to FOXJ1 mRNA destabilization and a severe loss of ciliated cells with an increase of neighboring goblet cells. Consistently, Fto knockout mice showed strong asthma-like phenotypes upon allergen challenge, a result owing to defective ciliated cells in the airway epithelium. Altogether, our study reveals a conserved role of the FTO-FOXJ1 axis in embryonic and homeostatic motile ciliogenesis.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Cílios/metabolismo , Desmetilação , Fatores de Transcrição Forkhead/genética , Organogênese , Estabilidade de RNA/genética , RNA Mensageiro/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Asma/patologia , Ciliopatias/patologia , Embrião de Mamíferos/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , RNA Mensageiro/metabolismo , Mucosa Respiratória/metabolismo , Xenopus laevis
11.
Artigo em Inglês | MEDLINE | ID: mdl-33669368

RESUMO

This study analyzed the psychological benefits of environmentally friendly edible insect restaurants, by proposing that three subdimensions of psychological benefits positively affect attitude. Attitude was hypothesized to play an important role in the formation of desire and two subdimensions of behavioral intentions: intentions to use and willingness to pay more. A research model was verified using responses from 419 respondents collected in Korea. Data analysis indicated that (1) warm glow, (2) self-expressive benefits, and (3) nature experiences form attitude and that attitude helps to increase desire, which in turn positively enhances behavioral intentions. The data analysis results supported the importance of the psychological benefits of environmentally friendly edible insect restaurants.


Assuntos
Insetos Comestíveis , Intenção , Animais , Insetos , República da Coreia , Restaurantes
12.
Sci Rep ; 11(1): 3346, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558639

RESUMO

There is a significant interest in designing therapeutic agents that can enhance ADCC and thereby improve clinical responses with approved antibodies. We recently reported the combination of an imidazoquinoline-based TLR7/8 agonist (522) with a monoclonal antibody improved ADCC in vitro and in vivo. In the present study, we tested several new small molecule TLR7/8 agonists that induce significantly higher cytokines compared to both the FDA-approved TLR7 agonist, imiquimod, and 522. We evaluated these agonists in combination with monoclonal antibody therapy, with the main goal of enhancing ADCC. Our studies show these TLR7/8 agonists induce robust pro-inflammatory cytokine secretion and activate NK cells. Specifically, we found the agonists 574 and 558 significantly enhanced NK cell-mediated ADCC in vitro as well as enhanced the anti-cancer efficacy of monoclonal antibodies in two different in vivo mouse models. Additionally, we found the agonists were able to stimulate CD8 T cells, likely indicative of an early adaptive immune response.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Imiquimode/farmacologia , Células Matadoras Naturais/imunologia , Neoplasias Experimentais , Receptor 7 Toll-Like/agonistas , Receptor 8 Toll-Like/agonistas , Células A549 , Animais , Humanos , Células Matadoras Naturais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/terapia , Receptor 7 Toll-Like/imunologia , Receptor 8 Toll-Like/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Nucleic Acids Res ; 49(5): e28, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33332543

RESUMO

RNA-protein interaction is central to post-transcriptional gene regulation. Identification of RNA-binding proteins relies mainly on UV-induced crosslinking (UVX) followed by the enrichment of RNA-protein conjugates and LC-MS/MS analysis. However, UVX has limited applicability in tissues of multicellular organisms due to its low penetration depth. Here, we introduce formaldehyde crosslinking (FAX) as an alternative chemical crosslinking for RNA interactome capture (RIC). Mild FAX captures RNA-protein interaction with high specificity and efficiency in cell culture. Unlike UVX-RIC, FAX-RIC robustly detects proteins that bind to structured RNAs or uracil-poor RNAs (e.g. AGO1, STAU1, UPF1, NCBP2, EIF4E, YTHDF proteins and PABP), broadening the coverage. Applied to Xenopus laevis oocytes and embryos, FAX-RIC provided comprehensive and unbiased RNA interactome, revealing dynamic remodeling of RNA-protein complexes. Notably, translation machinery changes during oocyte-to-embryo transition, for instance, from canonical eIF4E to noncanonical eIF4E3. Furthermore, using Mus musculus liver, we demonstrate that FAX-RIC is applicable to mammalian tissue samples. Taken together, we report that FAX can extend the RNA interactome profiling into multicellular organisms.


Assuntos
Proteômica/métodos , Ribonucleoproteínas/análise , Animais , Reagentes de Ligações Cruzadas , Embrião não Mamífero/metabolismo , Formaldeído , Células HeLa , Humanos , Fígado/metabolismo , Masculino , Camundongos , Oócitos/metabolismo , Peptídeos , Ribonucleoproteínas/metabolismo , Raios Ultravioleta , Xenopus laevis
14.
Artigo em Inglês | MEDLINE | ID: mdl-32517293

RESUMO

The purpose of this study is to apply the concept of a green image in order to explore how to form behavioral intentions in the context of eco-friendly edible insect restaurants. This study analyzed 444 samples collected in South Korea in order to evaluate the theoretical model including 12 hypotheses. The data analysis results showed that a green image has a positive influence on attitude. In addition, attitude helps to increase desire, which in turn positively affects two sub-dimensions of behavioral intentions, such as intentions to use and word-of-mouth intentions.


Assuntos
Insetos Comestíveis , Restaurantes , Animais , Atitude , Intenção , República da Coreia , Desenvolvimento Sustentável , Viagem
15.
Mol Pharm ; 17(6): 2109-2124, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383885

RESUMO

Activated natural killer (NK) cells can kill malignant tumor cells via granule exocytosis and secretion of IFN-γ, a key regulator of the TH1 response. Thus, mobilization of NK cells can augment cancer immunotherapy, particularly when mediated through antibody-dependent cellular cytotoxicity (ADCC). Stimulation of toll-like receptor (TLR)7/8 activity in dendritic cells promotes pro-inflammatory cytokine secretion and costimulatory molecule upregulation, both of which can potentiate NK cell activation. However, currently available TLR7/8 agonists exhibit unfavorable pharmacokinetics, limiting their in vivo efficacy. To enable efficient delivery to antigen-presenting cells, we encapsulated a novel imidazoquinoline-based TLR7/8 agonist in pH-responsive polymeric NPs. Enhanced costimulatory molecule expression on dendritic cells and a stronger pro-inflammatory cytokine response were observed with a NP-encapsulated agonist, compared to that with the soluble form. Treatment with NP-encapsulated agonists resulted in stronger in vivo cytotoxicity and prolonged activation of NK cells compared to that with a soluble agonist. In addition, TLR7/8 agonist-loaded NPs potentiated stronger NK cell degranulation, which resulted in enhanced in vitro and in vivo ADCC mediated by the epidermal growth factor receptor-targeting antibody cetuximab. TLR7/8 agonist-loaded NP treatment significantly enhanced the antitumor efficacy of cetuximab and an anti-HER2/neu antibody in mouse tumor models. Collectively, our data show that a pH-responsive NP-encapsulating TLR7/8 agonist could be used as a potent immunostimulatory adjuvant for antibody-based cancer immunotherapy by promoting NK cell activation.


Assuntos
Imunoterapia/métodos , Células Matadoras Naturais/metabolismo , Nanopartículas/química , Receptor 7 Toll-Like/agonistas , Receptor 8 Toll-Like/agonistas , Células A549 , Animais , Células Dendríticas/metabolismo , Citometria de Fluxo , Humanos , Imiquimode/química , Células Matadoras Naturais/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanomedicina/métodos
16.
Artigo em Inglês | MEDLINE | ID: mdl-31842426

RESUMO

The purpose of this study was to explore the antecedents and consequences of travelers' well-being perceptions in the context of a duty-free shop. For this, data were collected from 742 Chinese tourists who purchased goods at duty free shops while traveling in Korea within the past year using an online survey company's system in China. The results indicated that pragmatic, hedonic, and sociability experiences have a positive influence on travelers' well-being perceptions. In addition, travelers' well-being perceptions aided the enhancement of brand attitude and brand preference, which in turn positively affected word-of-mouth. Novelty is the originality of this study as very few studies on this topic are presented in the extant literature and practical implications are also discussed.


Assuntos
Comércio , Viagem/psicologia , Adulto , China , Feminino , Nível de Saúde , Humanos , Masculino , Percepção , República da Coreia , Inquéritos e Questionários
17.
Appl Surf Sci ; 4832019.
Artigo em Inglês | MEDLINE | ID: mdl-31555019

RESUMO

The friction characteristics of single-layer h-BN, MoS2, and graphene were systematically investigated via friction force microscopy measurements at various operational (e.g., normal force and sliding speed) and environmental (e.g., relative humidity and thermal annealing) conditions. The low friction characteristics of these single-layer materials were clearly observed from the normal force-dependent friction results, and their interfacial shear strengths were further estimated using a Hertz-plus-offset model. In addition, speed-dependent friction characteristics clearly demonstrated two regimes of friction as a function of sliding speed - the first is the logarithmic increase in friction with sliding speed regime at sliding speeds smaller than the critical speed and the second is the friction plateau regime at sliding speeds greater than the critical speed. Fundamental parameters such as effective shape of the interaction potential and its corrugation amplitude for these single-layer materials were characterized using the thermally-activated Prandtl-Tomlinson model. Moreover, friction of single-layer h-BN, MoS2, and graphene was found to increase with relative humidity and decrease with thermal annealing; these trends were attributed to the diffusion of water molecules to the interface between the single-layer materials and their substrates, which leads to an increase in the puckering effect at the tip-material interface and interaction potential corrugation. The enhanced puckering effect was verified via molecular dynamics simulations. Overall, the findings enable a comprehensive understanding of friction characteristics for several classes of two-dimensional materials, which is important to elucidate the feasibility of using these materials as protective and solid-lubricant coating layers for nanoscale devices.

18.
Sci Rep ; 9(1): 12492, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462656

RESUMO

In recent years, there have been significant advances in the treatment of breast cancer resulting in remarkably high survival rates. However, treatment options for metastatic triple negative breast cancer (TNBC) are quite limited due to a lack of identifiable, unique markers. Using a phage display-based whole cell biopanning procedure, we developed two human antibodies that bind to tumor cells with a metastatic TNBC phenotype. Our studies further identified domain 1 of HSPG2 (perlecan) protein as the cognate cell surface antigen bound by the antibody. Immunohistochemistry studies utilizing patient tissue samples revealed significant cell surface expression of HSPG2 in both primary tumors and metastatic lesions. Further, higher HSPG2 expression correlated with poor survival in TNBC. The affinity-matured antibody inhibited the growth of triple negative MDA-MB-231 tumors to a greater extent in nude mice than in NSG mice, pointing to the potential role of natural killer cell-mediated antibody-dependent cell cytotoxicity. This mechanism of action was confirmed through in vitro assays using mouse splenocytes and human peripheral blood mononuclear cells (PBMCs). These results suggest that HSPG2 is a promising target in metastatic TNBC and HSPG2-targeted antibodies could represent a potentially novel class of targeted therapeutics for TNBC.


Assuntos
Antineoplásicos Imunológicos , Proteoglicanas de Heparan Sulfato , Proteínas de Neoplasias , Neoplasias de Mama Triplo Negativas , Adulto , Animais , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antineoplásicos Imunológicos/imunologia , Antineoplásicos Imunológicos/farmacologia , Linhagem Celular Tumoral , Feminino , Proteoglicanas de Heparan Sulfato/genética , Proteoglicanas de Heparan Sulfato/imunologia , Humanos , Camundongos Nus , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Proteome Res ; 18(3): 1078-1087, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30638020

RESUMO

The deuterium, a frequently used stable isotope in isotopic labeling for quantitative proteomics, could deteriorate the accuracy and precision of proteome quantification owing to the retention time shift of deuterated peptides from the hydrogenated counterpart. We introduce a novel three-plexed peptide "diethylation" using only 13C isotopologues of acetaldehyde and demonstrate that the accuracy and precision of our method in proteome quantification are significantly superior to the conventional deuterium-based dimethylation labeling in both a single-shot and multidimensional LC-MS/MS analysis of the HeLa proteome. Furthermore, in time-resolved profiling of Xenopus laevis early embryogenesis, our 3-plexed diethylation outperformed isobaric labeling approaches in terms of the quantification accuracy or the number of protein identifications, generating more than two times more differentially expressed proteins. Our cost-effective and highly accurate 3-plexed diethylation method could contribute to various types of quantitative proteomics applications in which three of multiplexity would be sufficient.


Assuntos
Desenvolvimento Embrionário/genética , Proteoma/genética , Proteômica/métodos , Xenopus laevis/genética , Animais , Cromatografia Líquida , Deutério/química , Regulação da Expressão Gênica no Desenvolvimento/genética , Células HeLa , Humanos , Marcação por Isótopo , Espectrometria de Massas em Tandem , Xenopus laevis/crescimento & desenvolvimento
20.
J Pharmacol Exp Ther ; 370(3): 715-724, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30610006

RESUMO

Targeted drug delivery can significantly influence the efficacy of a drug. In the past decades, diverse drug-delivery technologies, including nano- and microparticles, co-crystals, and microneedles have been developed to maximize therapeutic efficacy and minimize undesired side effects of therapeutics. Nanoparticles-submicron-sized drug carriers-have been actively investigated for the delivery of antibiotics, nucleic acids, peptide/proteins, and chemotherapeutics. Recently, nanoparticles have gained attention as a vaccine delivery platform for tumor-associated antigens (TAAs) and/or vaccine adjuvants. Agonists of imidazoquinoline-based Toll-like receptor (TLR) 7/8 are potent cytokine inducers that are used as cancer vaccine adjuvants to elicit robust T-cell response by activating dendritic cells (DCs). Despite their in vitro potency, the translation of TLR7 agonists as cancer vaccine adjuvants in the clinic has been limited by their poor retention at the injection site. Therefore, a formulation that could improve the availability of TLR7/8 agonists to DCs via conventional vaccine administration routes (subcutaneous, intramuscular) can broaden the application of TLR7/8 agonists for cancer immunotherapy. Polymeric nanoparticles fabricated with poly(d,l-lactide-co-glycolide) (PLGA) can be an efficient TLR7/8 agonist delivery platform. PLGA is a biocompatible polymer, and nanoparticles prepared from this polymer are stable in saline and are small enough to be administered by subcutaneous or intramuscular injections. Furthermore, nanoparticulate TLR7/8 delivery can enhance DC uptake and facilitate lymphatic drainage, both of which can enhance the adjuvanticity of TLR7/8 agonists compared with soluble forms. In this review, we discuss the use of PLGA nanoparticles with TLR7/8 agonists for improving cancer immunotherapy.


Assuntos
Vacinas Anticâncer/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Receptor 7 Toll-Like/agonistas , Receptor 8 Toll-Like/agonistas , Animais , Vacinas Anticâncer/uso terapêutico , Humanos
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