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1.
Angew Chem Int Ed Engl ; 62(26): e202302111, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37088713

RESUMO

Compounds with redox activities have appealing applications in catalytic, electronic and magnetic properties, but the redox inert of polyoxoniobates (PONbs) significantly limits their applications for a long time. In this work, we are able to integrate organophosphate and lanthanide cluster into PONb to create the first family of inorganic-organic hybrid organophosphate-Ln-PONb composite clusters. These novel species not only present the first family of redox active PONbs that can be reduced to form long-lived "heteropoly blues" under ambient conditions, but also a new photochromic system. More importantly, the analyses of the electronic configurations and photochromic properties for a series of designed proof-of-concept PONbs models allow us to discover a D-f-A electron transfer mechanism, that is, photoinduced electron is transferred from a photosensitive organophosphate electron donor (D) to the NbV electron acceptor (A) through the unoccupied 4 f-orbitals of Ln (f). This work paves the way for developing diverse PONb-based redox materials and expanding the possibility of the applications of PONbs in the redox chemistry.


Assuntos
Elétrons , Transporte de Elétrons , Oxirredução , Catálise
2.
Inorg Chem ; 61(21): 8112-8116, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35588277

RESUMO

A rare 3D Indium-containing polyoxoniobate framework {H9[Cu(en)2(H2O)2][Cu(en)2]12[In(en)]5[Nb23-O65(OH)3(H2O)2]{Nb24O67(OH)2(H2O)3]2}·68H2O(1), based on the In-containing polyoxoniobate cluster, {[In(en)]5[Nb23O65(OH)3(H2O)2][Nb24O67(OH)2(H2O)3]2}35- ({In5Nb71}) and [Cu(en)2]2+ linkers has been successfully synthesized. The nest-like cluster {In5Nb71} is constructed from one brand-new V-shaped {Nb23O70}, two triangle-shaped {Nb24O72} and five [In(en)]3+. The [In(en)] fragments link {Nb24O72} and {Nb23O70} units into unique {In5Nb71}n helical pillars. The copper-amine complexes connect the {In5Nb71}n helical pillars into a three-dimensional (3D) inorganic-organic hybrid In-Cu-containing framework. This material also exhibits good ionic conductivity and vapor adsorption capacity properties.

3.
Acta Pharmacol Sin ; 43(4): 954-962, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34234269

RESUMO

Phage display technology allows for rapid selection of antibodies from the large repertoire of human antibody fragments displayed on phages. However, antibody fragments should be converted to IgG for biological characterizations and affinity of antibodies obtained from phage display library is frequently not sufficient for efficient use in clinical settings. Here, we describe a new approach that combines phage and mammalian cell display, enabling simultaneous affinity screening of full-length IgG antibodies. Using this strategy, we successfully obtained a novel germline-like anti-TIM-3 monoclonal antibody named m101, which was revealed to be a potent anti-TIM-3 therapeutic monoclonal antibody via in vitro and in vivo experiments, indicating its effectiveness and power. Thus, this platform can help develop new monoclonal antibody therapeutics with high affinity and low immunogenicity.


Assuntos
Anticorpos Monoclonais , Bacteriófagos , Animais , Técnicas de Visualização da Superfície Celular , Células Germinativas , Humanos , Mamíferos , Biblioteca de Peptídeos
4.
J Virol ; 93(20)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31375583

RESUMO

Early human immunodeficiency virus type 1 (HIV-1) treatment during the acute period of infection can significantly limit the seeding of viral reservoirs and modify the course of disease. However, while a number of HIV-1 broadly neutralizing antibodies (bnAbs) have demonstrated remarkable efficacy as prophylaxis in macaques chronically infected with simian-human immunodeficiency virus (SHIV), intriguingly, their inhibitory effects were largely attenuated in the acute period of SHIV infection. To investigate the mechanism for the disparate performance of bnAbs in different periods of SHIV infection, we used LSEVh-LS-F, a bispecific bnAb targeting the CD4 binding site and CD4-induced epitopes, as a representative bnAb and assessed its potential therapeutic benefit in controlling virus replication in acutely or chronically SHIV-infected macaques. We found that a single infusion of LSEVh-LS-F resulted in rapid decline of plasma viral loads to undetectable levels without emergence of viral resistance in the chronically infected macaques. In contrast, the inhibitory effect was robust but transient in the acutely infected macaques, despite the fact that all macaques had comparable plasma viral loads initially. Infusing multiple doses of LSEVh-LS-F did not extend its inhibitory duration. Furthermore, the pharmacokinetics of the infused LSEVh-LS-F in the acutely SHIV-infected macaques significantly differed from that in the uninfected or chronically infected macaques. Host SHIV-specific immune responses may play a role in the viremia-dependent pharmacokinetics. Our results highlight the correlation between the fast clearance of infused bnAbs and the treatment failure in the acute period of SHIV infection and may have important implications for the therapeutic use of bnAbs to treat acute HIV infections.IMPORTANCE Currently, there is no bnAb-based monotherapy that has been reported to clear the virus in the acute SHIV infection period. Since early HIV treatment is considered critical to restricting the establishment of viral reservoirs, investigation into the mechanism for treatment failure in acutely infected macaques would be important for the therapeutic use of bnAbs and eventually towards the functional cure of HIV/AIDS. Here we report the comparative study of the therapeutic efficacy of a bnAb in acutely and chronically SHIV-infected macaques. This study revealed the correlation between the fast clearance of infused bnAbs and treatment failure during the acute period of infection.


Assuntos
Anticorpos Antivirais/imunologia , Antivirais/farmacologia , Anticorpos Amplamente Neutralizantes/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Antivirais/uso terapêutico , Interações Hospedeiro-Patógeno/imunologia , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico
9.
Int J Med Sci ; 14(11): 1049-1053, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29104457

RESUMO

Melanin is a normal production protecting skin from environment-causing damage. Plants produce some agents in response to their environment. These agents could be applied in cosmetic production. Some Chinese herbals have immunomodulatory activities and modulate the symptoms of several diseases. Melanogenesis represents a complex group of conditions that are thought to be mediated through a complex network of regulatory processes. Previously, some studies found that the extracts of Astragalus membranaceus (PG2) regulated immunity and supported hematopoiesis. Herein, we want to determine the molecular mechanisms by which PG2 inhibits melanogenesis in B16F10 melanoma cells. The cellular melanin contents and expression of melanogenesis-related protein, including microphthalmia associated transcription factor (MITF) and tyrosinase were significantly reduced after PG2 treatment. Moreover, PG2 increased phosphorylation of ERK, without affecting phosphorylation of p38. These results suggested that PG2 as a new target in reducing hyperpigmentation through the ERK signal pathway. PG2 has potential for cosmetic usage in the future.


Assuntos
Astragalus propinquus/química , Medicamentos de Ervas Chinesas/administração & dosagem , Melanoma Experimental/tratamento farmacológico , Animais , Medicamentos de Ervas Chinesas/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melaninas/metabolismo , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Fator de Transcrição Associado à Microftalmia/genética , Monofenol Mono-Oxigenase/genética , Fosforilação
10.
Int J Med Sci ; 14(12): 1181-1188, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29104473

RESUMO

Upregulation of connexin 43 (Cx43) showed potential in enhancing immune surveillance that was suppressed in the tumor microenvironment. The expression of indoleamine 2, 3-dioxygenase (IDO) is one of the crucial factors contributing to tumor immune tolerance by depletion of tryptophan and IDO-mediated tryptophan metabolites. Here, we aim to investigate the role of Cx43 in IDO production in murine tumor by using Cx43 inducers. Resveratrol (trans-3, 5, 4 '-trihydroxystilbene) is a natural plant-derived polyphenol possessing positive effect against cancer. Salmonella enterica serovar choleraesuis (S.C.) was proved to target and inhibit tumor growth. Both of them regulated Cx43 expression in tumor cells and led to either chemosensitizing or immune-activating. In this study, the correlation between Cx43 and IDO were determined by the treatment of resveratrol and S.C. Our data showed an increase in Cx43 while IDO protein and IDO-mediated inhibited effects on T cell decreased after tumor cells are given with resveratrol and S.C. TREATMENTS: All of which could be inhibited once the expression of Cx43 was blocked. Cx43 involved in IDO regulation might be useful in developing IDO-targeted cancer immune therapy.


Assuntos
Conexina 43/imunologia , Tolerância Imunológica/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Neoplasias/imunologia , Linfócitos T/imunologia , Animais , Linhagem Celular Tumoral , Conexina 43/genética , Conexina 43/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Tolerância Imunológica/efeitos dos fármacos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos , Neoplasias/patologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Resveratrol , Salmonella enterica/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Estilbenos/farmacologia , Regulação para Cima
11.
Tumour Biol ; 37(1): 673-83, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26242266

RESUMO

Growing evidence demonstrates that long noncoding RNAs (lncRNAs) are involved in the progression of various cancers including glioma. Nuclear enriched abundant transcript 1 (NEAT1), an essential lncRNA for the formation of nuclear body paraspeckles, was not fully explored in glioma. We aimed to determine the expression, roles, and functional mechanisms of NEAT1 in the progression of glioma. By real-time PCR, we suggested that NEAT1 was upregulated in glioma tissues than noncancerous brain tissues. Knockdown of NEAT1 reduced glioma cell proliferation, invasion, and migration. RNA immunoprecipitation assay combined with luciferase reporter assay confirmed miR-449b-5p-specific binding to NEAT1. Furthermore, we verified that c-Met was a directly target of miR-449b-5p. Rescue assays demonstrated NEAT1 functions a molecular sponge for miR-449b-5p and leads to the upregulation of c-Met. This regulation menchaism promotes glioma pathogenesis and may provide a potential target for the prognosis and treatment of glioma.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-met/genética , RNA Longo não Codificante/genética , Animais , Apoptose/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Camundongos , Modelos Biológicos , Interferência de RNA , Regulação para Cima
12.
Vaccines (Basel) ; 12(7)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39066395

RESUMO

mRNA vaccines were successfully developed and approved for emergency use to fight coronavirus disease 2019. However, the effect of DNA vaccines against SARS-CoV-2 is considerably lower than that of mRNA vaccines. A pyro-drive jet injector (PJI) efficiently delivers plasmid DNA intradermally into animal models. Here, we compared the immunogenic potential of DNA and mRNA vaccines in mice using the same platform. PJI was used to deliver naked mRNA and pDNA and their efficacy in inducing antigen expression and immune responses was assessed. Our results showed that PJI efficiently delivered mRNA into the skin, and a smaller effective dose than that of pDNA injection was required to achieve similar levels of antigen expression. The PJI-delivered CpG-free pDNA vaccine efficiently induced antigen-specific antibody production and a cell-mediated IFN-γ response compared to the mRNA vaccine, as well as the upregulation of inflammatory cytokines (IL-6, IFN-γ, and IL-1ß) in the skin and lymph nodes. However, the intradermal mRNA vaccine was significantly less immunogenic than the standard intramuscular mRNA-lipid nanoparticle vaccine, despite equivalent mRNA dosages. Improvements in lipid nanoparticle and mRNA technology have revolutionized mRNA vaccines, and DNA vaccines can be similarly modified for higher clinical efficacy.

13.
Nanoscale ; 16(26): 12420-12423, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38888289

RESUMO

Four different structural compositions of organophosphate, 3d transition metal, 4f lanthanide and polyoxoniobate (PONb) are unified in a system for the first time to form a new type of organophosphate 3d-4f heterometallic inorganic-organic hybrid PONb nanowire. Interesting magnetic anisotropy and slow magnetic relaxation are found in the PONb nanowire.

14.
Int J Cancer ; 133(8): 1926-35, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23558669

RESUMO

The use of preferentially replicating bacteria as oncolytic agents is one of the innovative approaches for the treatment of cancer. The capability of Salmonella to disperse within tumors and hence to delay tumor growth was augmented when combined with chemotherapy. This work is warranted to elucidate the underlying mechanism of antitumor effects by the combination therapy of Salmonella and cisplatin. The presence of functional gap junctions is highly relevant for the success of chemotherapy. Following Salmonella treatment, dose- and time-dependent upregulation of connexin 43 (Cx43) expressions were observed. Moreover, Salmonella significantly enhanced gap intercellular communication (GJIC), as revealed by the fluorescent dye scrape loading assay. To study the pathway underlying these Salmonella-induced effects, we found that Salmonella induced a significant increase in mitogen-activated protein kinases (MAPK) signaling pathways. The Salmonella-induced upregulation of Cx43 was prevented by treatment of cells with the phosphorylated p38 inhibitor, but not phosphorylated extracellular signal-regulated kinase (pERK) inhibitor or phosphorylated c-jun N terminal kinase (pJNK) inhibitor. Specific knockdown of Cx43 had an inhibitory effect on GJIC and resulted in a reduction of cell death after Salmonella and cisplatin treatment. Our results suggest that accumulation of Salmonella in tumor sites leads to increase Cx43 gap junction communication and enhances the combination of Salmonella and cisplatin therapeutic effects.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Conexina 43/metabolismo , Neoplasias/tratamento farmacológico , Salmonella/metabolismo , Animais , Apoptose/efeitos dos fármacos , Terapia Biológica , Comunicação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Conexina 43/genética , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Junções Comunicantes/microbiologia , Imidazóis/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias/microbiologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
15.
Mar Drugs ; 11(6): 1899-908, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23736765

RESUMO

Reducing hyperpigmentation has been a big issue for years. Even though pigmentation is a normal mechanism protecting skin from UV-causing DNA damage and oxidative stress, it is still an aesthetic problem for many people. Bacteria can produce some compounds in response to their environment. These compounds are widely used in cosmetic and pharmaceutical applications. Some probiotics have immunomodulatory activities and modulate the symptoms of several diseases. Previously, we found that the extracts of Rhodobacter sphaeroides (Lycogen™) inhibited nitric oxide production and inducible nitric-oxide synthase expression in activated macrophages. In this study, we sought to investigate an anti-melanogenic signaling pathway in α-melanocyte stimulating hormone (α-MSH)-treated B16F10 melanoma cells and zebrafish. Treatment with Lycogen™ inhibited the cellular melanin contents and expression of melanogenesis-related protein, including microphthalmia-associated transcription factor (MITF) and tyrosinase in B16F10 cells. Moreover, Lycogen™ reduced phosphorylation of MEK/ERK without affecting phosphorylation of p38. Meanwhile, Lycogen™ decreased zebrafish melanin expression in a dose-dependent manner. These findings establish Lycogen™ as a new target in melanogenesis and suggest a mechanism of action through the ERK signaling pathway. Our results suggested that Lycogen™ may have potential cosmetic usage in the future.


Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melaninas/metabolismo , Rhodobacter sphaeroides/química , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Hiperpigmentação/tratamento farmacológico , Melanoma Experimental , Camundongos , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Fosforilação/efeitos dos fármacos , Peixe-Zebra , alfa-MSH/metabolismo
16.
Sci Signal ; 16(803): eade3599, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37725663

RESUMO

RUBCN (also known as Rubicon) was originally identified as a negative regulator of autophagy, a process by which cells degrade and recycle damaged components or organelles and that requires the activity of the class III PI3K VPS34 and the mTORC1 protein complex. Here, we characterized the role of a shorter isoform, RUBCN100, as an autophagy-promoting factor in B cells. RUBCN100 was translated from alternative translation initiation sites and lacked the RUN domain of the longer, previously characterized RUBCN130 isoform. Specific deficiency of RUBCN130 in B cells enhanced autophagy, which promoted memory B cell generation. In contrast to RUBCN130, which is localized in late endosomes and lysosomes and suppresses the enzymatic activity of VPS34, an effect thought to mediated by its RUN domain, RUBCN100 was preferentially located in early endosomes and enhanced VPS34 activity, presumably because of the absence of the RUN domain. Furthermore, RUBCN100, but not RUBCN130, enhanced autophagy and suppressed mTORC1 activation. Our findings reveal that the opposing roles of two RUBCN isoforms are critical for autophagy regulation and memory B cell differentiation.


Assuntos
Linfócitos B , Células B de Memória , Autofagia , Isoformas de Proteínas/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética
17.
J Healthc Eng ; 2021: 2064162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950438

RESUMO

To explore the role of circulating blood miR-155 and miR-21 in promoting acute pancreatitis (AP) and evaluating the risk stratification of pancreatitis. In this experiment, 70 patients with AP treated in our hospital from October 2019 to December 2020 were included in the research group (RG), and the blood of 52 healthy cases was collected and they were included in the control group (CG). The expression of miR-155 and miR-21 in circulating blood was observed in the two groups. The diagnostic efficacy of miR-155 and miR-21 in AP was observed. The risk factors of patients with AP were observed. The expression of serum gastrointestinal hormones was observed in the two groups. The GAS and VIP in RG were higher than those in CG, while MTL and CCK were lower than those in CG. Moreover, the detection level of mild, moderate, severe, and critical patients was also significantly different (P < 0.05). The expression of miR-155 and miR-21 in circulating blood of RG was significantly lower than that of CG (P < 0.05), and the area under the miR-155 curve was 0.775 and the area under the miR-21 curve was 0.832. Alcoholism, GAS, VIP, MTL, CCK, miR-155, and miR-21 were the risk factors of patients. miR-155 and miR-21 show low expression in the serum of patients. The lower the expression, the more serious the disease. They are closely related to the development of AP. miR-155 and miR-21 have good diagnostic efficacy by ROC analysis, and they are expected to become effective indicators for the diagnosis and treatment of AP in the future.


Assuntos
MicroRNAs/sangue , Pancreatite , Doença Aguda , Humanos , MicroRNAs/genética , Pancreatite/diagnóstico , Pancreatite/genética , Curva ROC , Medição de Risco
18.
Chem Commun (Camb) ; 57(69): 8624-8627, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34369518

RESUMO

A series of 3d-4f heterometallic cluster incorporated polyoxoniobates (PONbs) with different magnetic properties were first made and characterized. This work not only provides a promising strategy to make new heterometallic cluster incorporated PONbs but also demonstrates an ideal model to probe how transition-metal ions influence the magnetic property of PONbs.

19.
Chem Commun (Camb) ; 57(38): 4702-4705, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33977969

RESUMO

Nanoscale {Nb68O200} cages have been successfully employed as flexible and stable secondary building units to combine with bridging copper-amine complexes to construct two proton conductive polyoxoniobate frameworks, demonstrating a promising strategy for making new porous materials.

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