Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 94
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Anal Chem ; 96(18): 6947-6957, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38656889

RESUMO

Life-threatening allergic reactions to food allergens, particularly peanut protein Ara h1, are a growing public health concern affecting millions of people worldwide. Thus, accurate and rapid detection is necessary for allergen labeling and dietary guidance and ultimately preventing allergic incidents. Herein, we present a novel ratiometric fluorescence aptasensor based on multivalent aptamer-encoded DNA flowers (Mul-DNFs) for the high-stability and sensitive detection of allergen Ara h1. The flower-shaped Mul-DNFs were spontaneously packaged using ultralong polymeric DNA amplicons driven by a rolling circle amplification reaction, which contains a large number of Ara h1 specific recognition units and has excellent binding properties. Furthermore, dual-color fluorescence-labeled Mul-DNFs probes were developed by hybridizing them with Cy3- and Cy5-labeled complementary DNA (cDNA) to serve as a ratiometric fluorescence aptasensor platform based on fluorescence resonance energy transfer. Benefiting from the combined merits of the extraordinary synergistic multivalent binding ability of Mul-DNFs, the excellent specificity of the aptamer, and the sensitivity of the ratiometric sensor to avoid exogenous interference. The developed ratiometric aptasensor showed excellent linearity (0.05-2000 ng mL-1) with a limit of detection of 0.02 ng mL-1. Additionally, the developed ratiometric fluorescence aptasensor was utilized for quantifying the presence of Ara h1 in milk, infant milk powder, cookies, bread, and chocolate with recoveries of 95.7-106.3%. The proposed ratiometric aptasensor is expected to be a prospective universal aptasensor platform for the rapid, sensitive, and accurate determination of food and environmental hazards.


Assuntos
Alérgenos , Antígenos de Plantas , Aptâmeros de Nucleotídeos , Transferência Ressonante de Energia de Fluorescência , Proteínas de Membrana , Aptâmeros de Nucleotídeos/química , Alérgenos/análise , Antígenos de Plantas/análise , Técnicas Biossensoriais/métodos , DNA/química , Animais , Limite de Detecção , Glicoproteínas/análise , Glicoproteínas/química , Corantes Fluorescentes/química , Proteínas de Plantas/análise , Proteínas de Plantas/química
2.
Anal Chem ; 96(10): 4103-4110, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38427614

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a 5 year survival rate less than 12%. This malignancy is closely related to the unique tumor microenvironment (TME), which is characterized by a hypovascular and hyperdense extracellular matrix, making it difficult for drugs to permeate the tumor center. Near-infrared fluorescence (NIRF) imaging, which has high sensitivity and resolution, may improve the survival rate of PDAC patients. In this study, we first used JS-K (O2-(2,4-dinitrophenyl) 1-[(4-ethoxycarbonyl) piperazine-1-yl] diazene-1-ium-1,2-diolate) to specifically dilate blood vessels within the TME of PDAC patients and subsequently injected IR820-PEG-MNPs (IPM NPs) to diagnose and treat orthotopic PDAC. We found that JS-K promoted the accumulation of IPM NPs in orthotopic Pan02 tumor-bearing mice and was able to increase the tumor signal-to-background ratio (SBR) in the orthotopic PDAC area by 41.5%. In addition, surgical navigation in orthotopic Pan02 tumor-bearing mice and complete tumor resection based on fluorescence imaging were achieved with a detection sensitivity of 81.0%. Moreover, we verified the feasibility of the combination of laparoscopy and photothermal ablation (PTA) for the treatment of PDAC. Finally, we demonstrated that IPM NPs had greater affinity for human PDAC tissues than for normal pancreatic tissues ex vivo, preliminarily highlighting the potential for clinical translation of these NPs. In conclusion, we developed and validated a novel sequential delivery strategy that promotes the accumulation of nanoagents in the tumor area and can be used for the diagnosis and treatment of PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Melaninas , Medicina de Precisão , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Imagem Óptica/métodos , Linhagem Celular Tumoral , Microambiente Tumoral
3.
Chemistry ; 30(49): e202401990, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38923670

RESUMO

The preparation of capsid-like nanoshells and the elucidation of their formation pathways are crucial for the application potential of capsid-like nanomaterials. In this study, we have prepared biomimetic capsid-like nanoshells (CLNs) through the solution self-assembly of poly (ß-phenethyl-L-aspartate) homopolypeptide (PPLA). The formation of CLNs is governed by an aggregation-fusion mechanism. Initially, PPLA molecules self-assemble into small spherical assemblies as subunits and the initial nuclei are formed through fusing some subunits. Subsequently, additional subunits rapidly fuse onto these nuclei, leading to the growth of full or partial CLNs during the growth phase. Moreover, the suitable condition benefiting CLNs formation is clarified by a morphological phase diagram based on the initial PPLA concentration against water content. Molecular-level measurements suggest that the molecular flexibility of PPLA is a key factor in the arrangement and fusion of subunits for the formation of CLNs. These findings offer new perspectives for a deeper understanding of the formation pathways of capsid-like nanoshells derived from synthetic polymers.


Assuntos
Materiais Biomiméticos , Nanoconchas , Peptídeos , Peptídeos/química , Materiais Biomiméticos/química , Nanoconchas/química , Capsídeo/química , Biomimética
4.
BMC Public Health ; 24(1): 2670, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350112

RESUMO

OBJECTIVE: The relationship between vitamin D3 and asthma remains controversial. However, previous studies have largely overlooked the impact of epi-25-(OH)-vitamin D3. This study aims to investigate the effects of different forms of vitamin D3 on asthma attack in adults. METHODS: In this cross-sectional study, a total of 3,873 eligible adult participants were extracted from the national health and nutrition examination survey (NHANES) database from 2007 to 2018. Based on quartiles method, different levels of vitamin D were divided into four groups (Quartile 1-4). Bivariate correlation analysis was performed for vitamin D and covariates to avoid multicollinearity. Multivariate logistic regression was used to investigate the association between serum levels of vitamin D3 (epi-25-(OH)-vitamin D3 and 25-(OH)-vitamin D3) and asthma attack, adjusting for covariates including age, gender, race, length of time in the U.S., house poverty income ratio (PIR), education level, smoking history, hypertension history, and diabetes history. The ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 was used for secondary analysis of its association with asthma attack. The outcomes were assessed by odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among the 3,873 eligible adults American with asthma, 1,508 (38.94%) had experienced at least one acute asthma attack in the past year. There was no significant correlation between vitamin D and covariates. After adjusting for covariates including age, gender, race, length of time in the U.S., house poverty income ratio (PIR), education level, smoking history, hypertension history and diabetes history, we found a positive correlation between the ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 and asthma attack. Additionally, a high ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 was more common among elder, male, of normal weight, non-Hispanic American, have a long time stay in the U.S., a high house PIR, and a history of hypertension individuals. CONCLUSION: Our findings suggest that attention should be given to asthma attack associated with a high ratio of epi-25-(OH)-vitamin D3 to 25-(OH)-vitamin D3 in American adults who are elderly, male, of normal weight, non-Hispanic Americans, have long-term residence in the U.S., a high house PIR, and a history of hypertension.


Assuntos
Asma , Inquéritos Nutricionais , Humanos , Asma/epidemiologia , Asma/sangue , Masculino , Feminino , Estados Unidos/epidemiologia , Estudos Transversais , Adulto , Pessoa de Meia-Idade , Calcifediol/sangue , Fatores de Risco , Idoso , Adulto Jovem
5.
Mikrochim Acta ; 191(3): 130, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351361

RESUMO

After optimizing the original aptamer sequence by truncation strategy, a magnetic separation-assisted DNAzyme-driven 3D DNA walker fluorescent aptasensor was developed for detecting the food-borne pathogen Cronobacter species. Iron oxide magnetic nanoparticles (MNPs) modified with a hybrid of truncated aptamer probe and DNAzyme strand (AP-E1) denoted as MNPs@AP-E1, were employed as capture probes. Simultaneously, a DNAzyme-driven 3D-DNA walker was utilized as the signal amplification element. The substrate strand (Sub) was conjugated with the gold nanoparticles (AuNPs), resulting in the formation of AuNPs@Sub, which served as a 3D walking track. In the presence of the target bacteria and Mg2+, E1-DNAzyme was activated and moved along AuNPs@Sub, continuously releasing the signal probe. Under optimized conditions, a strong linear correlation was observed for Cronobacter sakazakii (C. sakazakii) in the concentration range 101 to 106 CFU mL-1, with a low detection limit of 2 CFU mL-1. The fluorescence signal responses for different Cronobacter species exhibited insignificant differences, with a relative standard deviation of 3.6%. Moreover, the aptasensor was successfully applied to determine  C. sakazakii in real samples with recoveries of 92.86%-108.33%. Therefore, the novel method could be a good candidate for ultra-sensitive and selective detection of Cronobacter species without complex manipulation.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Cronobacter , DNA Catalítico , Nanopartículas Metálicas , DNA Catalítico/genética , Ouro , Cronobacter/genética , Aptâmeros de Nucleotídeos/genética , Técnicas Biossensoriais/métodos , Limite de Detecção , DNA/genética
6.
Small ; 19(30): e2300843, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37035959

RESUMO

Lithium-sulfur battery (LSB) is widely regarded as the most promising next-generation energy storage system owing to its high theoretical capacity and low cost. However, the practical application of LSBs is mainly hampered by the low electronic conductivity of the sulfur cathode and the notorious "shuttle effect", which lead to high voltage polarization, severe over-charge behavior, and rapid capacity decay. To address these issues, a novel sulfur reservoir is synthesized by coating polypyrrole (PPy) thin film on hollow layered double hydroxide (LDH) (PPy@LDH). After compositing with sulfur, such PPy@LDH-S cathode shows a multi-functional effect to reserve lithium polysulfides (LiPSs). In addition, the unique architecture provides sufficient inner space to encapsulate the volume expansion and enhances the reaction kinetics of sulfur-based redox chemistry. Theoretical calculations have illustrated that the PPy@LDH has shown stronger chemical adsorption capability for LiPSs than those of porous carbon and LDH, preventing the shuttling of LiPSs and enhancing the nucleation affinity of liquid-solid conversion. As a result, the PPy@LDH-S electrode delivers a stable cycling performance and a superior rate capability. Flexible battery has demonstrated this PPy@LDH-S electrode can work properly with treatments of bending, folding, and even twisting, paving the way for wearable devices and flexible electronics.

7.
Biomed Eng Online ; 22(1): 21, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864414

RESUMO

BACKGROUND: The development and innovation of biomechanical measurement methods provide a solution to the problems in ski jumping research. At present, research on ski jumping mostly focuses on the local technical characteristics of different phases, but studies on the technology transition process are less. OBJECTIVES: This study aims to evaluate a measurement system (i.e. the merging of 2D video recording, inertial measurement unit and wireless pressure insole) that can capture a wide range of sport performance and focus on the key transition technical characteristics. METHODS: The application validity of the Xsens motion capture system in ski jumping was verified under field conditions by comparing the lower limb joint angles of eight professional ski jumpers during the takeoff phase collected by different motion capture systems (Xsens and Simi high-speed camera). Subsequently, the key transition technical characteristics of eight ski jumpers were captured on the basis of the aforementioned measurement system. RESULTS: Validation results indicated that the joint angle point-by-point curve during the takeoff phase was highly correlated and had excellent agreement (0.966 ≤ r ≤ 0.998, P < 0.001). Joint root-mean-square error (RMSE) differences between model calculations were 5.967° for hip, 6.856° for knee and 4.009° for ankle. CONCLUSIONS: Compared with 2D video recording, the Xsens system shows excellent agreement to ski jumping. Furthermore, the established measurement system can effectively capture the key transition technical characteristics of athletes, particularly in the dynamic changes of straight turn into arc in inrun, the adjustment of body posture and ski movement during early flight and landing preparation.


Assuntos
Articulação do Tornozelo , Extremidade Inferior , Humanos , Fenômenos Biomecânicos , Atletas , Tecnologia
8.
BMC Pregnancy Childbirth ; 23(1): 189, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934238

RESUMO

BACKGROUND: Acute pancreatitis in pregnancy (APIP) with a high risk of death is extremely harmful to mother and fetus. There are few models specifically designed to assess the severity of APIP. Our study aimed to establish a clinical model for early prediction of severity of APIP. METHODS: A retrospective study in a total of 188 patients with APIP was enrolled. The hematological indicators, IAP (intra-abdominal pressure) and clinical data were obtained for statistical analysis and prediction model construction. RESULTS: According to univariate and multivariate logistic regression analysis, we found that red cell distribution width (RDW), neutrophil-lymphocyte ratio (NLR) and Intra-abdominal pressure (IAP) are prediction indexes of the severity in APIP (p-value < 0.05). Our novel clinical prediction model was created by based on the above three risk factors and showed superior predictive power in primary cohort (AUC = 0.895) and validation cohort (AUC = 0.863). A nomogram for severe acute pancreatitis in pregnancy (SAPIP) was created based on the three indicators. The nomogram was well-calibrated. CONCLUSION: RDW, NLR and IAP were the independent risk factors of APIP. Our clinical prediction model of severity in APIP based on RDW, NLR and IAP with predictive evaluation is accurate and effective.


Assuntos
Pancreatite , Gravidez , Feminino , Humanos , Pancreatite/diagnóstico , Pancreatite/etiologia , Neutrófilos , Índices de Eritrócitos , Estudos Retrospectivos , Doença Aguda , Modelos Estatísticos , Prognóstico , Linfócitos
9.
J Nanobiotechnology ; 21(1): 489, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38111035

RESUMO

Orthotopic advanced hepatic tumor resection without precise location and preoperative downstaging may cause clinical postoperative recurrence and metastasis. Early accurate monitoring and tumor size reduction based on the multifunctional diagnostic-therapeutic integration platform could improve real-time imaging-guided resection efficacy. Here, a Near-Infrared II/Photoacoustic Imaging/Magnetic Resonance Imaging (NIR-II/PAI/MRI) organic nanoplatform IRFEP-FA-DOTA-Gd (IFDG) is developed for integrated diagnosis and treatment of orthotopic hepatic tumor. The IFDG is designed rationally based on the core "S-D-A-D-S" NIR-II probe IRFEP modified with folic acid (FA) for active tumor targeting and Gd-DOTA agent for MR imaging. The IFDG exhibits several advantages, including efficient tumor tissue accumulation, good tumor margin imaging effect, and excellent photothermal conversion effect. Therefore, the IFDG could realize accurate long-term monitoring and photothermal therapy non-invasively of the hepatic tumor to reduce its size. Next, the complete resection of the hepatic tumor in situ lesions could be realized by the intraoperative real-time NIR-II imaging guidance. Notably, the preoperative downstaging strategy is confirmed to lower the postoperative recurrence rate of the liver cancer patients under middle and advanced stage effectively with fewer side effects. Overall, the designed nanoplatform demonstrates great potential as a diagnostic-therapeutic integration platform for precise imaging-guided surgical navigation of orthotopic hepatic tumors with a low recurrence rate after surgery, providing a paradigm for diagnosing and treating the advanced tumors in the future clinical translation application.


Assuntos
Neoplasias Hepáticas , Nanopartículas , Cirurgia Assistida por Computador , Humanos , Fototerapia , Imageamento por Ressonância Magnética/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Linhagem Celular Tumoral
10.
Mikrochim Acta ; 190(11): 443, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848735

RESUMO

A novel ternary Y-DNA walker amplification strategy designed fluorescence aptasensor based on Au@SiO2@Fe3O4 nanomaterials for ultrasensitive and specific ochratoxin A detection in food samples is presented. Au@SiO2@Fe3O4 nanomaterials provide the loading platform as well as separation and recovery properties for the ternary Y-DNA walker. The ternary Y-DNA walker is designed to be driven by Nb.BbvCI cleaving a large number of FAM probes to achieve signal amplification. Since Ochratoxin A (OTA) can bind to the constituent aptamer in the ternary Y-DNA walker, adding OTA will destroy the structure of the ternary Y-DNA walker, thereby inhibiting the driving process of the walker. After optimization of various parameters, a standard curve was obtained from 100 to 0.05 ng·mL-1 of OTA with the limit of determination of 0.027 ng·mL-1. The spiked recovery of peanut samples by this method was 82.00-93.30%, and the aptasensor showed excellent specificity and long-term stability. This simple, robust, and scalable oligonucleotide chain-based ternary Y-DNA walker can provide a general signal amplification strategy for trace analysis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanoestruturas , Dióxido de Silício/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , DNA
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA