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1.
Nano Lett ; 24(10): 3133-3141, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477056

RESUMO

Liquid manipulation is essential for daily life and modern industry, and it is widely used in various fields, including seawater desalination, microfluidic robots, and biomedical engineering. Nevertheless, the current research focuses on the manipulation of individual droplets. There are a few projects for water film management. Here, we proposed a facile method of wind-triggered water film self-sculpturing based on a heterogeneous wettability surface, which is achieved by the femtosecond laser direct writing technology and femtosecond laser deposition. Under the conditions of various airflow velocities and water film thicknesses, three distinct behaviors of the water film were analyzed. As a result, when the water film thickness is lower than 4.9 mm, the self-sculpture process will occur until the whole superhydrophobic surface dewetting. Four potential applications are demonstrated, including encryption, oil containers, reconfigurable patterning, and self-splitting devices. This work provides a new approach for manipulating a water film of fluid control engineering.

2.
Nat Chem Biol ; 17(7): 767-775, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33723431

RESUMO

The transcriptional coactivator Yes-associated protein 1 (YAP) orchestrates a proproliferative transcriptional program that controls the fate of somatic stem cells and the regenerative responses of certain tissues. As such, agents that activate YAP may hold therapeutic potential in disease states exacerbated by insufficient proliferative repair. Here we report the discovery of a small molecule, termed PY-60, which robustly activates YAP transcriptional activity in vitro and promotes YAP-dependent expansion of epidermal keratinocytes in mouse following topical drug administration. Chemical proteomics revealed the relevant target of PY-60 to be annexin A2 (ANXA2), a protein that directly associates with YAP at the cell membrane in response to increased cell density. PY-60 treatment liberates ANXA2 from the membrane, ultimately promoting a phosphatase-bound, nonphosphorylated and transcriptionally active form of YAP. This work reveals ANXA2 as a previously undescribed, druggable component of the Hippo pathway and suggests a mechanistic rationale to promote regenerative repair in disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Anexina A2/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/metabolismo , Administração Tópica , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/metabolismo , Animais , Anexina A2/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Proteínas de Sinalização YAP
3.
Int J Mol Sci ; 24(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37373246

RESUMO

The aim of this study is to explore the potential targets and molecular mechanism of matrine (MAT) against aging. Bioinformatic-based network pharmacology was used to investigate the aging-related targets and MAT-treated targets. A total of 193 potential genes of MAT against aging were obtained and then the top 10 key genes (cyclin D1, cyclin-dependent kinase 1, Cyclin A2, androgen receptor, Poly [ADP-ribose] polymerase-1 (PARP1), histone-lysine N-methyltransferase, albumin, mammalian target of rapamycin, histone deacetylase 2, and matrix metalloproteinase 9) were filtered by the molecular complex detection, maximal clique centrality (MMC) algorithm, and degree. The Metascape tool was used for analyzing biological processes and pathways of the top 10 key genes. The main biological processes were response to an inorganic substance and cellular response to chemical stress (including cellular response to oxidative stress). The major pathways were involved in cellular senescence and the cell cycle. After an analysis of major biological processes and pathways, it appears that PARP1/nicotinamide adenine dinucleotide (NAD+)-mediated cellular senescence may play an important role in MAT against aging. Molecular docking, molecular dynamics simulation, and in vivo study were used for further investigation. MAT could interact with the cavity of the PARP1 protein with the binding energy at -8.5 kcal/mol. Results from molecular dynamics simulations showed that the PARP1-MAT complex was more stable than PARP1 alone and that the binding-free energy of the PARP1-MAT complex was -15.962 kcal/mol. The in vivo study showed that MAT could significantly increase the NAD+ level of the liver of d-gal-induced aging mice. Therefore, MAT could interfere with aging through the PARP1/NAD+-mediated cellular senescence signaling pathway.


Assuntos
Matrinas , NAD , Camundongos , Animais , NAD/metabolismo , Simulação de Acoplamento Molecular , Poli(ADP-Ribose) Polimerase-1/metabolismo , Envelhecimento , Estresse Oxidativo , Mamíferos/metabolismo
4.
Int J Mol Sci ; 24(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686218

RESUMO

Dysregulation of clusterin (CLU) has been demonstrated in many cancers and has been proposed as a regulator of carcinogenesis. However, the roles of CLU in gliomas remain unclear. The expression of CLU was assessed using TIMER2.0, GEPIA2, and R package 4.2.1 software, leveraging data from TCGA and/or GTEx databases. Survival analysis and Cox regression were employed to investigate the prognostic significance of CLU. Immune infiltration was evaluated utilizing TIMER2.0, ESTIMATE, and CIBERSORT. The findings reveal the dysregulated expression of CLU in many cancers, with a marked increase observed in glioblastoma and lower-grade glioma (LGG). High CLU expression indicated worse survival outcomes and was an independent risk factor for the prognosis in LGG patients. CLU was involved in immune status as evidenced by its strong correlations with immune and stromal scores and the infiltration levels of multiple immune cells. Additionally, CLU was co-expressed with multiple immune-related genes, and high CLU expression was associated with the activation of immune-related pathways, such as binding to the antigen/immunoglobulin receptor and aiding the cytokine and cytokine receptor interaction. In conclusion, CLU appears to play crucial roles in tumor immunity within gliomas, highlighting its potential as a biomarker or target in glioma immunotherapy.


Assuntos
Glioblastoma , Glioma , Humanos , Carcinogênese , Clusterina/genética , Glioma/genética , Prognóstico
5.
Geriatr Nurs ; 49: 101-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36470103

RESUMO

Social frailty is a geriatric public health problem that deeply affects healthy aging. Currently, evidence on the prevalence and factors associated with social frailty in older adults remains unclear. Our study aims to estimate the prevalence and related factors of social frailty in older adults. This study retrieved nine electronic databases searched through July 5th, 2022. The prevalence of social frailty was pooled using Stata software. It was found that older adults suffered from a "moderate" level of social frailty. We found a higher prevalence of social frailty in the United Kingdom, Greece, Croatia, The Netherlands, and Spain, in people over 75 years, in hospitals, and during the Coronavirus Disease 2019 (COVID-19). We believed that countries, age, research sites, and the pandemic of COVID-19 were influencing factors of social frailty among older adults. These findings may provide a theoretical basis for the development of ameliorating social frailty among older adults.


Assuntos
COVID-19 , Fragilidade , Humanos , Idoso , Fragilidade/epidemiologia , Prevalência , COVID-19/epidemiologia , Hospitais , Países Baixos/epidemiologia , Idoso Fragilizado
6.
Bioconjug Chem ; 31(4): 1167-1176, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32243137

RESUMO

Oxyntomodulin (OXM) is an intestinal peptide hormone that activates both glucagon-like peptide-1 (GLP-1) and glucagon (GCG) receptors. The natural peptide reduces body weight in obese subjects and exhibits direct acute glucoregulatory effects in patients with type II diabetes. However, the clinical utility of OXM is limited due to its lower in vitro potency and short in vivo half-life. To overcome these issues, we developed stapled, long-acting, and highly potent OXM analogs with balanced activities at both GLP-1 and GCG receptors. The lead molecule O14 exhibits potent and long-lasting effects on glucose control, body weight loss, and reduction of hepatic fat reduction in DIO mice. Importantly, O14 significantly reversed hepatic steatosis; reduced liver weight, total cholesterol, and hepatic triglycerides; and improved markers of liver function in a nonalcoholic steatohepatitis (NASH) mouse model. A symmetrical version of the peptide was also shown to be more efficacious and long-lasting in controlling glucose than semaglutide and the clinical candidate cotadutide in wild-type mice, highlighting the utility of our designs of the dual agonist as a potential new therapy for diabetes and liver diseases.


Assuntos
Peso Corporal/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Oxintomodulina/farmacologia , Oxintomodulina/farmacocinética , Animais , Glicemia/metabolismo , Colesterol/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/sangue , Oxintomodulina/uso terapêutico , Triglicerídeos/metabolismo
7.
Biochem Biophys Res Commun ; 519(3): 497-504, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31530388

RESUMO

Emerging evidence has uncovered the extremely important roles of long noncoding RNAs (lncRNAs) in the progression of malignant tumors which includes numerous processes of gene regulation. LncRNA NR2F1-AS1 has been confirmed to have close correlation with the tumorigenesis of diverse cancers. However, the underlying regulatory function of it on esophageal squamous cell carcinoma (ESCC) progression is poorly known and thus needs more elucidations. In this study, a markedly elevated expression of NR2F1-AS1 was discovered in ESCC cells. Functional assays demonstrated that NR2F1-AS1 deficiency repressed ESCC progression. Molecular mechanism tests verified that knockdown of NR2F1-AS1 could lower the expression of GLI2 (a key protein molecule of Hedgehog signaling pathway) in ESCC. Additionally, NR2F1-AS1 was confirmed to facilitate ESCC progression via activation of Hedgehog signaling pathway. NR2F1-AS1 activated Hedgehog signaling pathway by regulating GLI2 to upregulate NR2F1 expression in ESCC. Besides, NR2F1 was testified to activate NR2F1-AS1 transcription in ESCC. Final rescue assays further demonstrated that NR2F1 upregulation could reverse the NR2F1-AS1 knockdown-mediated function on ESCC progression. Briefly, NR2F1-induced NR2F1-AS1 promotes ESCC progression through activation of Hedgehog signaling pathway.


Assuntos
Fator I de Transcrição COUP/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Proteínas Hedgehog/metabolismo , RNA Antissenso/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Células Cultivadas , Progressão da Doença , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Humanos , RNA Antissenso/genética , RNA Longo não Codificante/genética
8.
Bioconjug Chem ; 30(1): 83-89, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30543420

RESUMO

Peptide hormone relaxin-2, a member of the insulin family of peptides, plays a key role in hemodynamics and renal function and has shown preclinical efficacy in multiple disease models, including acute heart failure, fibrosis, preeclampsia, and corneal wound healing. Recently, serelaxin, a recombinant version of relaxin-2, has been studied in a large phase 3 clinical trial (RELAX-AHF-2) for acute decompensated heart failure patients with disappointing outcome. The poor in vivo half-life of relaxin-2 may have limited its therapeutic efficacy and long-term cardiovascular benefit. Herein, we have developed a semisynthetic methodology and generated potent, fatty acid-conjugated relaxin analogs with long-acting pharmacokinetic (PK) profile in rodents. The enhanced PK properties translated into improved and long-lasting pharmacodynamic effect in pubic ligament elongation (PLE) studies. The resultant novel relaxin analog, R9-13, represents the first long-acting relaxin-2 analog and could potentially improve the clinical efficacy and outcome for this important peptide hormone. This semisynthetic methodology could also be applied to other cysteine-rich peptides and proteins for half-life extension.


Assuntos
Desenho de Fármacos , Lipídeos/química , Relaxina/química , Relaxina/uso terapêutico , Sequência de Aminoácidos , Animais , Meia-Vida , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Relaxina/farmacocinética
9.
Nat Chem Biol ; 13(8): 845-849, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28604693

RESUMO

Tyrosine phosphorylation is a common protein post-translational modification that plays a critical role in signal transduction and the regulation of many cellular processes. Using a propeptide strategy to increase cellular uptake of O-phosphotyrosine (pTyr) and its nonhydrolyzable analog 4-phosphomethyl-L-phenylalanine (Pmp), we identified an orthogonal aminoacyl-tRNA synthetase-tRNA pair that allows site-specific incorporation of both pTyr and Pmp into recombinant proteins in response to the amber stop codon in Escherichia coli in good yields. The X-ray structure of the synthetase reveals a reconfigured substrate-binding site, formed by nonconservative mutations and substantial local structural perturbations. We demonstrate the utility of this method by introducing Pmp into a putative phosphorylation site and determining the affinities of the individual variants for the substrate 3BP2. In summary, this work provides a useful recombinant tool to dissect the biological functions of tyrosine phosphorylation at specific sites in the proteome.


Assuntos
Códon sem Sentido/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Fosfotirosina/análogos & derivados , Fosfotirosina/genética , Cristalografia por Raios X , Ligases/química , Ligases/metabolismo , Modelos Moleculares , Estrutura Molecular , Fosforilação , Fosfotirosina/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
10.
Mol Pharm ; 16(1): 371-381, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30543441

RESUMO

Rapeseed protein hydrolysates have recently shown in vitro antioxidant and anti-inflammatory activities. However, scant data exist about their in vivo activities. Here, we report that the peptide DHNNPQIR (hereinafter referred to as RAP-8), a bioactive peptide originated from rapeseed protein, exhibits excellent in vivo efficacy in mouse models of nonalcoholic steatohepatitis (NASH) and hepatic fibrosis. We demonstrated that RAP-8 significantly reduced hepatic steatosis and improved insulin resistance and lipid metabolism. Furthermore, RAP-8 showed markedly reduced hepatic inflammation, fibrosis, liver injury, and metabolic deterioration. In particular, RAP-8 directly suppressed fibrosis-associated gene expression, including α-smooth muscle actin (α-Sma) and collagen type I (Col-1α) in the liver of mice in vivo. In addtion, RAP-8 significantly decreased macrophage infiltration and reduced pro-inflammatory cytokines secretion. Finally, we found that RAP-8 administration significantly decreased oxidative stress-induced apoptosis in liver injury induced by CCl4. Therefore, our results suggest that RAP-8 could be available for treatment of NASH and NASH-related metabolic disorders as a potential therapeutic candidate.


Assuntos
Antioxidantes/uso terapêutico , Doenças Metabólicas/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas de Plantas/uso terapêutico , Animais , Brassica rapa/química , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/uso terapêutico , Proteínas S100/uso terapêutico
11.
Metab Brain Dis ; 34(1): 173-181, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30406376

RESUMO

The present study was designed to evaluate the effects of matrine (MAT) on scopolamine (SCOP)-induced learning and memory impairment. After successive oral administration of MAT to mice for three days at doses of 0.4, 2, and 10 mg/kg, we assessed improvements in learning and memory and investigated the mechanism of action of SCOP-induced amnesia. Donepezil at a dose of 3 mg/kg was used as a standard memory enhancer. MAT significantly improved SCOP-induced learning and memory impairment in novel object recognition and Y-maze tests at doses of 0.4, 2, and 10 mg/kg. Furthermore, MAT inhibited acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities and decreased oxidative stress in the brain, as evidenced by increased total antioxidant capacity, total superoxide dismutase levels, and catalase activities as well as decreased malondialdehyde levels. Additionally, there was a significant negative correlation between the percentage of spontaneous alternation in the Y maze and AChE activity in the cortex and hippocampus. MAT ameliorated SCOP-induced amnesia by the inhibition of both AChE/BuChE activities and oxidative stress. This study provides further evidence to encourage the development of MAT as a drug for the prevention or treatment of Alzheimer's disease.


Assuntos
Alcaloides/uso terapêutico , Amnésia/tratamento farmacológico , Antioxidantes/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Quinolizinas/uso terapêutico , Alcaloides/farmacologia , Amnésia/induzido quimicamente , Amnésia/metabolismo , Animais , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catalase/metabolismo , Inibidores da Colinesterase/farmacologia , Masculino , Malondialdeído/metabolismo , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Fármacos Neuroprotetores/farmacologia , Quinolizinas/farmacologia , Escopolamina , Superóxido Dismutase/metabolismo , Matrinas
12.
Proc Natl Acad Sci U S A ; 113(13): 3615-20, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26976568

RESUMO

Thiopeptides are a subclass of ribosomally synthesized and posttranslationally modified peptides (RiPPs) with complex molecular architectures and an array of biological activities, including potent antimicrobial activity. Here we report the generation of thiopeptides containing noncanonical amino acids (ncAAs) by introducing orthogonal amber suppressor aminoacyl-tRNA synthetase/tRNA pairs into a thiocillin producer strain of Bacillus cereus .We demonstrate that thiopeptide variants containing ncAAs with bioorthogonal chemical reactivity can be further postbiosynthetically modified with biophysical probes, including fluorophores and photo-cross-linkers. This work allows the site-specific incorporation of ncAAs into thiopeptides to increase their structural diversity and probe their biological activity; similar approaches can likely be applied to other classes of RiPPs.


Assuntos
Aminoácidos/química , Peptídeos/química , Substituição de Aminoácidos , Aminoácidos/genética , Aminoácidos/metabolismo , Bacillus cereus/genética , Bacillus cereus/metabolismo , Estrutura Molecular , Mutagênese Sítio-Dirigida , Peptídeos/genética , Peptídeos/metabolismo , Engenharia de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Massas em Tandem
13.
Proc Natl Acad Sci U S A ; 113(15): 4140-5, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27035989

RESUMO

Antidiabetic treatments aiming to reduce body weight are currently gaining increased interest. Exendin-4, a glucagon-like peptide-1 (GLP-1) receptor agonist administered twice daily via s.c. injection, improves glycemic control, often with associated weight reduction. To further improve the therapeutic efficacy of exendin-4, we have developed a novel peptide engineering strategy that incorporates a serum protein binding motif onto a covalent side-chain staple and applied to the peptide to enhance its helicity and, as a consequence, its potency and serum half-life. We demonstrated that one of the resulting peptides, E6, has significantly improved half-life and glucose tolerance in an oral glucose tolerance test in rodents. Chronic treatment of E6 significantly decreased body weight and fasting blood glucose, improved lipid metabolism, and also reduced hepatic steatosis in diet-induced obese mice. Moreover, the high potency of E6 allowed us to administer this peptide using a dissolvable microstructure-based transdermal delivery system. Pharmacokinetic and pharmacodynamic studies in guinea pigs showed that a single 5-min application of a microstructure system containing E6 significantly improved glucose tolerance for 96 h. This delivery strategy may offer an effective and patient-friendly alternative to currently marketed GLP-1 injectables and can likely be extended to other peptide hormones.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/química , Engenharia de Proteínas , Administração Cutânea , Sequência de Aminoácidos , Peso Corporal , Dicroísmo Circular , AMP Cíclico/biossíntese , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/farmacocinética , Teste de Tolerância a Glucose , Células HEK293 , Humanos
14.
Proc Natl Acad Sci U S A ; 110(27): E2510-7, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23776209

RESUMO

A cell-based phenotypic screen for inhibitors of biofilm formation in mycobacteria identified the small molecule TCA1, which has bactericidal activity against both drug-susceptible and -resistant Mycobacterium tuberculosis (Mtb) and sterilizes Mtb in vitro combined with rifampicin or isoniazid. In addition, TCA1 has bactericidal activity against nonreplicating Mtb in vitro and is efficacious in acute and chronic Mtb infection mouse models both alone and combined with rifampicin or isoniazid. Transcriptional analysis revealed that TCA1 down-regulates genes known to be involved in Mtb persistence. Genetic and affinity-based methods identified decaprenyl-phosphoryl-ß-D-ribofuranose oxidoreductase DprE1 and MoeW, enzymes involved in cell wall and molybdenum cofactor biosynthesis, respectively, as targets responsible for the activity of TCA1. These in vitro and in vivo results indicate that this compound functions by a unique mechanism and suggest that TCA1 may lead to the development of a class of antituberculosis agents.


Assuntos
Antituberculosos/farmacologia , Benzotiazóis/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tiofenos/farmacologia , Tuberculose Pulmonar/tratamento farmacológico , Oxirredutases do Álcool , Sequência de Aminoácidos , Animais , Antituberculosos/administração & dosagem , Antituberculosos/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Benzotiazóis/administração & dosagem , Benzotiazóis/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Carboidratos Epimerases/antagonistas & inibidores , Carboidratos Epimerases/química , Carboidratos Epimerases/genética , Farmacorresistência Bacteriana , Feminino , Genes Bacterianos , Ensaios de Triagem em Larga Escala , Isoniazida/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , Oxirredutases/antagonistas & inibidores , Oxirredutases/química , Oxirredutases/genética , Rifampina/administração & dosagem , Tiofenos/administração & dosagem , Tiofenos/química , Tuberculose Pulmonar/microbiologia
15.
Angew Chem Int Ed Engl ; 55(40): 12475-8, 2016 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-27595986

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor (GLP-1R), glucagon (GCG) receptor (GCGR), and glucose-dependent insulinotropic polypeptide (GIP, also known as gastric inhibitory polypeptide) receptor (GIPR), are three metabolically related peptide hormone receptors. A novel approach to the generation of multifunctional antibody agonists that activate these receptors has been developed. Native or engineered peptide agonists for GLP-1R, GCGR, and GIPR were fused to the N-terminus of the heavy chain or light chain of an antibody, either alone or in pairwise combinations. The fusion proteins have similar in vitro biological activities on the cognate receptors as the corresponding peptides, but circa 100-fold longer plasma half-lives. The GLP-1R mono agonist and GLP-1R/GCGR dual agonist antibodies both exhibit potent effects on glucose control and body weight reduction in mice, with the dual agonist antibody showing enhanced activity in the latter.


Assuntos
Anticorpos/imunologia , Peptídeo 1 Semelhante ao Glucagon/agonistas , Glucagon/agonistas , Receptores dos Hormônios Gastrointestinais/agonistas , Animais , Anticorpos/genética , Anticorpos/metabolismo , Peso Corporal/efeitos dos fármacos , Feminino , Glucagon/imunologia , Peptídeo 1 Semelhante ao Glucagon/imunologia , Células HEK293 , Meia-Vida , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Cadeias Pesadas de Imunoglobulinas/metabolismo , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/imunologia , Cadeias Leves de Imunoglobulina/metabolismo , Camundongos , Camundongos Obesos , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Engenharia de Proteínas , Ratos , Ratos Sprague-Dawley , Receptores dos Hormônios Gastrointestinais/imunologia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia
16.
Angew Chem Int Ed Engl ; 55(26): 7520-4, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27145250

RESUMO

Chimeric antigen receptor T (CAR-T) cells have demonstrated promising results against hematological malignancies, but have encountered significant challenges in translation to solid tumors. To overcome these hurdles, we have developed a switchable CAR-T cell platform in which the activity of the engineered cell is controlled by dosage of an antibody-based switch. Herein, we apply this approach to Her2-expressing breast cancers by engineering switch molecules through site-specific incorporation of FITC or grafting of a peptide neo-epitope (PNE) into the anti-Her2 antibody trastuzumab (clone 4D5). We demonstrate that both switch formats can be readily optimized to redirect CAR-T cells (specific for the corresponding FITC or PNE) to Her2-expressing tumor cells, and afford dose-titratable activation of CAR-T cells ex vivo and complete clearance of the tumor in rodent xenograft models. This strategy may facilitate the application of immunotherapy to solid tumors by affording comparable efficacy with improved safety owing to switch-based control of the CAR-T response.


Assuntos
Neoplasias da Mama/terapia , Genes de Troca , Imunoterapia , Receptores de Antígenos de Linfócitos T , Animais , Relação Dose-Resposta a Droga , Feminino , Genes de Troca/genética , Xenoenxertos , Humanos , Camundongos , Receptor ErbB-2/efeitos dos fármacos , Receptor ErbB-2/metabolismo
17.
Chembiochem ; 16(5): 712-24, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25652106

RESUMO

The completion of the human genome sequencing project has provided a wealth of new information regarding the genomic blueprint of the cell. Although, to date, there are roughly 20,000 genes in the human genome, the functions of only a handful of proteins are clear. The major challenge lies in translating genomic information into an understanding of their cellular functions. The recently developed activity-based protein profiling (ABPP) is an unconventional approach that is complementary for gene expression analysis and an ideal utensil in decoding this overflow of genomic information. This approach makes use of synthetic small molecules that covalently modify a set of related proteins and subsequently facilitates identification of the target protein, enabling rapid biochemical analysis and inhibitor discovery. This tutorial review introduces recent advances in the field of ABPP and its applications.


Assuntos
Sondas Moleculares/química , Proteínas/análise , Proteômica , Perfilação da Expressão Gênica , Humanos , Estrutura Molecular , Proteínas/metabolismo
18.
PLoS One ; 19(5): e0302305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722994

RESUMO

This article proposes an integer ambiguity determination method based on Beidou system-reflectometry (Beidou-R) observations of the carrier phase at the B1I and B3I frequencies. To enhance the accuracy of sea surface height (SSH) estimation, this study introduces a parallel filtering algorithm and an adaptive iterative fusion algorithm, enabling data fusion based on the variance at B1I and B3I frequencies. To validate and evaluate the proposed method, a coastal experiment was conducted at the Shenxian River. In this experiment, reflected signals from GEO and IGSO satellites were collected. Data analysis reveals that the method is effective, demonstrating that the root mean square error (RMSE) of SSH achieves 2.85 cm and 2.89 cm for PRN 04 and PRN 33, respectively. Furthermore, the impact of the elevation angle on measurement accuracy is analyzed. This study aims to propose a method to enhance coastal sea surface height estimation, offering potential advancements in sea surface altimetry.


Assuntos
Algoritmos , Oceanos e Mares , Monitoramento Ambiental/métodos
19.
Front Public Health ; 12: 1401161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39022407

RESUMO

Introduction: Rescuing individuals at sea is a pressing global public health issue, garnering substantial attention from emergency medicine researchers with a focus on improving prevention and control strategies. This study aims to develop a Dynamic Bayesian Networks (DBN) model utilizing maritime emergency incident data and compare its forecasting accuracy to Auto-regressive Integrated Moving Average (ARIMA) and Seasonal Auto-regressive Integrated Moving Average (SARIMA) models. Methods: In this research, we analyzed the count of cases managed by five hospitals in Hainan Province from January 2016 to December 2020 in the context of maritime emergency care. We employed diverse approaches to construct and calibrate ARIMA, SARIMA, and DBN models. These models were subsequently utilized to forecast the number of emergency responders from January 2021 to December 2021. The study indicated that the ARIMA, SARIMA, and DBN models effectively modeled and forecasted Maritime Emergency Medical Service (EMS) patient data, accounting for seasonal variations. The predictive accuracy was evaluated using Mean Absolute Error (MAE), Root Mean Squared Error (RMSE), and Coefficient of Determination (R 2) as performance metrics. Results: In this study, the ARIMA, SARIMA, and DBN models reported RMSE of 5.75, 4.43, and 5.45; MAE of 4.13, 2.81, and 3.85; and R 2 values of 0.21, 0.54, and 0.44, respectively. MAE and RMSE assess the level of difference between the actual and predicted values. A smaller value indicates a more accurate model prediction. R 2 can compare the performance of models across different aspects, with a range of values from 0 to 1. A value closer to 1 signifies better model quality. As errors increase, R 2 moves further from the maximum value. The SARIMA model outperformed the others, demonstrating the lowest RMSE and MAE, alongside the highest R 2, during both modeling and forecasting. Analysis of predicted values and fitting plots reveals that, in most instances, SARIMA's predictions closely align with the actual number of rescues. Thus, SARIMA is superior in both fitting and forecasting, followed by the DBN model, with ARIMA showing the least accurate predictions. Discussion: While the DBN model adeptly captures variable correlations, the SARIMA model excels in forecasting maritime emergency cases. By comparing these models, we glean valuable insights into maritime emergency trends, facilitating the development of effective prevention and control strategies.


Assuntos
Teorema de Bayes , Previsões , Aprendizado de Máquina , Modelos Estatísticos , Humanos , China , Serviços Médicos de Emergência/estatística & dados numéricos , Navios/estatística & dados numéricos
20.
Polymers (Basel) ; 16(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39065335

RESUMO

The precast segmental column (PSC) has been proposed for reducing onsite construction time and minimizing impacts on traffic and the environment. It has been proven to have good seismic performance according to previous studies. However, due to the rocking behavior of the column, the toe of the bottom segment could experience excessive compressive damage. In addition, the commonly used steel rebars in the PSC could experience corrosion problems during the service life of the structure. Moreover, ordinary Portland cement concrete (OPC) is normally used in the construction of the PSC, but the manufacturing processes of the OPC could emit a lot of carbon dioxide. This paper investigates the seismic performance of PSCs incorporating Basalt Fiber Reinforced Polymer (BFRP) bars and geopolymer concrete (GPC) segments. To mitigate the concrete crushing damage of the segment, the BFRP sheet was used to wrap the bottom segment of one of the specimens. The results revealed that the BFRP-reinforced geopolymer concrete PSC exhibited good seismic performance with minimal damage and small residual displacement. Strengthening the bottom segment with BFRP wrapping proved to be effective in reducing concrete damage. As a result, the column with BFRP wrap demonstrated the ability to withstand ground motions with higher Peak Ground Acceleration (PGA) compared to the column without strengthening.

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