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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124193, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38569386

RESUMO

Osteoporosis is a significant health concern. While multiple techniques have been utilized to diagnose this condition, certain limitations still persist. Raman spectroscopy has shown promise in predicting bone strength in animal models, but its application to humans requires further investigation. In this study, we present an in vitro approach for predicting osteoporosis in 10 patients with hip fractures using Raman spectroscopy. Raman spectra were acquired from exposed femoral heads collected during surgery. Employing a leave-one-out cross-validated linear discriminant analysis (LOOCV-LDA), we achieved accurate classification (90 %) between osteoporotic and osteopenia groups. Additionally, a LOOCV partial least squares regression (PLSR) analysis based on the complete Raman spectra demonstrated a significant prediction (r2 = 0.84, p < 0.05) of bone mineral density as measured by dual X-ray absorptiometry (DXA). To the best of our knowledge, this study represents the first successful demonstration of Raman spectroscopy correlating with osteoporotic status in humans.


Assuntos
Fraturas do Quadril , Osteoporose , Animais , Humanos , Análise Espectral Raman , Osteoporose/diagnóstico , Densidade Óssea , Absorciometria de Fóton/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38561564

RESUMO

PURPOSE: To assess Black women's exposure to and appraisal of racism-related stress during the postpartum period and to distinguish its impact on three indicators of postpartum mood and anxiety disorders (PMADs) symptoms. METHODS: Data from the Black Mothers' Mental Wellness Study (N = 231) and linear regression models estimated the associations between racism-related stress and the PMAD indicators: 3-item Edinburgh Postnatal Depression Scale (EPDS-3), 8-item Patient Health Questionnaire (PHQ-8), and PHQ-15. RESULTS: The majority of participants (80.5%, N = 186) experienced racism a few times a year or more, of which 37.1% (N = 69) were bothered somewhat and 19.3% (N = 36) a lot. Racism-related stress, income, level of education, and history of mental health diagnosis explained greater variance in PMAD symptoms as measured by the PHQ-8 score (R2 = 0.58, p = < 0.001) compared to the EPDS-3 (R2 = 0.46, p = < 0.001) or the PHQ-15 (R2 = 0.14, p = 0.035). CONCLUSIONS: Racism is a stressor for Black women living in Los Angeles County, California. Racism-related stress and emotional expression of PMAD symptoms were salient to the postpartum mental health of the Black women in this study. Findings from this study suggest that the PHQ-8 should be used to assess how racism impacts Black women's postpartum mental health.

3.
Food Chem ; 448: 139127, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608399

RESUMO

To address the food safety issues caused by toxins, we established a fluorescent copper nanocluster biosensor based on magnetic aptamer for the visual and quantitative detection of ZEN. Specifically, we utilized the docking-aided rational tailoring (DART) strategy to analyze intermolecular force and interaction sites between zearalenone (ZEN) and the aptamer, and optimize the long-chain aptamer step by step to enhance the binding affinity by 3.4 times. The magnetic bead-modified aptamer underwent conformational changes when competing with complementary sequences to bind with ZEN. Then, the released complementary sequences will be amplified in template-free mode with the presence of the terminal deoxynucleotidyl transferase (TdT), and generating T-rich sequences as the core sequences for the luminescence of copper nanoclusters. The luminescence could be visualized and quantitatively detected through ultraviolet irradiation. The proposed label-free aptasensor exhibited high sensitivity and specificity, with a low limit of detection (LOD) of 0.1 ng/mL.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Cobre , Zearalenona , Zearalenona/análise , Zearalenona/química , Cobre/química , Técnicas Biossensoriais/instrumentação , Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise , Limite de Detecção , Simulação de Acoplamento Molecular , Nanopartículas Metálicas/química , Fluorescência
4.
EBioMedicine ; 102: 105042, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471990

RESUMO

BACKGROUND: An ongoing important need exists to rapidly develop novel therapeutics for COVID-19 that will retain antiviral efficacy in the setting of rapidly evolving SARS-CoV-2 variants and potential future development of resistance of SARS-COV-2 to remdesivir and protease inhibitors. To date, there is no FDA-approved treatment for post-exposure prophylaxis against SAR-CoV-2. We have shown that the mitochondrial antioxidant mitoquinone/mitoquinol mesylate (Mito-MES), a dietary supplement, has antiviral activity against SARS-CoV-2 in vitro and in SARS-CoV-2 infected K18-hACE2 mice. METHODS: In this exploratory, pragmatic open label clinical trial (ClinicalTrials.gov identifier NCT05381454), we studied whether Mito-MES is an effective post-exposure prophylaxis treatment in people who had high-grade unmasked exposures to SARS-CoV-2 within 5 days prior to study entry. Participants were enrolled in real-world setting in Los Angeles, United States between May 1 and December 1, 2022 and were assigned to either mito-MES 20 mg daily for 14 days (n = 40) or no mito-MES (controls) (n = 40). The primary endpoint was development of SARS-CoV-2 infection based on 4 COVID-19 diagnostic tests [rapid antigen tests (RATs) or PCR] performed during the study period (14 days post exposure). FINDINGS: Out of 40 (23 females; 57.5%) study participants who took Mito-MES, 12 (30%) developed SARS-CoV-2 infection compared to 30 of the 40 controls (75%) (difference -45.0%, 95% confidence intervals (CI): -64.5%, -25.5%). Out of 40 (19 females; 47.5%) study participants in the control group, 30 (75.0%) had at least one positive COVID-19 diagnostic test and 23 (57.5%) were symptomatic. With regards to key secondary outcomes, among symptomatic SARS-CoV-2 infections, the median duration of viral symptoms was lower in the Mito-MES group (median 3.0, 95% CI 2.75, 3.25) compared to the control group (median 5.0, 95% CI 4.0, 7.0). None of the study participants was hospitalized or required oxygen therapy. Mito-MES was well tolerated and no serious side effect was reported in any study participant. INTERPRETATION: This work describes antiviral activity of mito-MES in humans. Mito-MES was well tolerated in our study population and attenuated transmission of SARS-CoV-2 infection. Given established safety of Mito-MES in humans, our results suggest that randomized control clinical trials of Mito-MES as post-exposure prophylaxis against SARS-CoV-2 infection are warranted. FUNDING: This work was supported in part by National Institutes of Health grant R01AG059501 (TK), National Institutes of Health grant R01AG059502 04S1 (TK), NIH/National Center for Advancing Translational Sciences (NCATS) UCLA CTSI Grant Number UL1TR001881 and California HIV/AIDS Research Program grant OS17-LA-002 (TK).


Assuntos
COVID-19 , Compostos Organofosforados , Ubiquinona , Animais , Feminino , Humanos , Camundongos , Antivirais , COVID-19/prevenção & controle , Profilaxia Pós-Exposição , SARS-CoV-2 , Resultado do Tratamento , Ubiquinona/análogos & derivados
5.
Artigo em Inglês | MEDLINE | ID: mdl-38530523

RESUMO

This study explores the crucial contribution of the "Belt and Road" Initiative (BRI) in diminishing carbon intensity and facilitating progress towards carbon neutrality, addressing the pressing global issue of climate change. Given its status as the world's foremost carbon emitter, China encounters significant pressure to alleviate its emissions. Launched in 2013, the BRI emphasizes economic development along its route while highlighting environmental protection in the regions involved. Despite extensive analyses of the BRI's economic impact, its environmental consequences have received insufficient attention, hindering a comprehensive evaluation of the initiative and obstructing the constructing of an environmentally optimal road. Empirical findings reveal a substantial reduction in carbon emission intensity in provinces along the BRI route, with robustness tests (change the time window period and dynamic effect) validating result consistency. The BRI achieves this reduction by alleviating congestion, enhancing transportation infrastructure, fostering commuting agglomeration, optimizing energy utilization, and lowering carbon intensity. Further analysis uncovers a mediating chain effect, establishing a conduction mechanism of "BRI brings on transportation infrastructure effect and then leads to travel agglomeration effect and then to congestion improvement effect and then to energy utilization effect and then eventuates carbon intensity reduction." This study offers crucial insights for policymakers aiming to make informed decisions towards the green road construction of the BRI, contributing to global efforts to combat climate change.

6.
Chaos ; 34(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38305055

RESUMO

The purpose of this paper was to study the evolution and dynamic characteristics of the helical gear system co-existence response considering the occurrence of de-meshing and reverse impact under lubrication conditions. The double-three tooth alternate meshing model of a helical gear was established, and the time-varying geometric parameters, motion parameters, and load distribution of positive meshing and reverse impact were analyzed, respectively. The variation of oil film parameters and the coupling between oil film stiffness and meshing stiffness of a gear system were studied according to the equivalent lubrication model of a helical gear. Considering the phenomenon that the meshing state changed from positive meshing to de-meshing and reverse impact, the dynamics model was established. The global bifurcation diagram, the attraction domain, the phase portrait, and the Poincaré section were used to analyze the evolution of a coexistence response and dynamic characteristics with helical gear system parameters.

7.
PLoS One ; 19(2): e0296121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38354124

RESUMO

In recent years, the world has been facing severe challenges from climate change and environmental issues, with carbon dioxide emissions being considered one of the main driving factors. Many studies have proven that activities in various industries and fields have a significant impact on carbon dioxide emissions. However, few studies have explored the impact of gender on carbon dioxide emissions. This study aims to explore the potential impact of gender diversity on carbon dioxide emissions in the boards of directors of developed and emerging market enterprises. In addition, we also analyzed how board cultural diversity affects carbon dioxide emissions. We searched two European indices provided by Morgan Stanley Capital International (MSCI) from the Bloomberg database and conducted empirical analysis. We selected the MSCI index and MSCI emerging market index from 2010 to 2019 as samples and thoroughly cleaned up the data by removing any observations containing missing information on any variables. Statistical methods such as t-test, ordinary least squares, panel data analysis, regression analysis, and robustness testing were used for statistical analysis. At the same time, differential testing was conducted on sensitive and non-sensitive sectors, and the average representation of female boards in sensitive industries was low. The research results show that the proportion of female members on a company's board of directors is negatively correlated with carbon dioxide emissions. This discovery is consistent with the legitimacy theory advocating for gender equality and environmental sustainability, emphasizing the importance of gender diversity in reducing greenhouse gas emissions. However, agency theory suggests that diversity may lead to internal conflicts within a company, leading to agency costs and information asymmetry. The research results show a negative correlation between board cultural diversity and carbon dioxide emissions, indicating the potential challenge of board cultural diversity. This study provides important insights for decision-makers and managers, not only inspiring corporate social responsibility and environmental policy formulation, but also of great significance for academic research in the field of climate change. Our research findings help deepen our understanding of the factors that affect carbon dioxide emissions in different sectors and countries, while also expanding the research field between gender diversity, cultural diversity, and environmental sustainability. Although this study still needs to be further expanded and deepened, it provides useful insights into the relationship between board gender and cultural diversity and carbon dioxide emissions.


Assuntos
Dióxido de Carbono , Gases de Efeito Estufa , Feminino , Humanos , Dióxido de Carbono/análise , Gases de Efeito Estufa/análise , Mudança Climática , Política Ambiental , Indústrias , Desenvolvimento Econômico
8.
Talanta ; 271: 125664, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38237281

RESUMO

We presented a label-free fluorescent biosensor based on magnetic dual-aptamer allosteric regulation of ß-lactoglobulin (ß-LG) detection. The bovine serum albumin (BSA) acted as the bridge to connect amino-modified magnetic beads and aptamer, which synthesized pyramid-type probes (MBAP) with high capture and reduced nonspecific adsorption. Moreover, the original aptamer was tailored and then designed as a bivalent aptamer to fabricate allosteric signal probes (ASP). The ASP can both specifically capture ß-LG and output the fluorescence signal. The detection mechanism is as follows. The combination of the dual-aptamer and ß-LG triggered the allosteric change, resulting in the release of SYBR Green (SG I) from the allosteric signal probe and change signals. This method exhibits a broad linear detection range from 10 ng/mL to 1 mg/mL and the limit of detection reaches as low as 8.06 ng/mL. This study provides a highly generalizable strategy for protein biomolecular detection via replacing different target aptamers.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Lactoglobulinas , Regulação Alostérica , Corantes , Técnicas Biossensoriais/métodos
9.
Anal Chim Acta ; 1279: 341827, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827645

RESUMO

Cadmium is a heavy metal that is exceedingly hazardous to humans and can enter the body through tainted food or drink, causing severe harm. It is critical to develop a technology for detecting cadmium in food and water that is sensitive and accurate. One such approach, which employs nucleases, is uncommon. A cadmium(II) turn-on biosensor was successfully created in this work using repetitive cleavage of certain specific nucleases for signal conversion and sophisticated stem-loop qPCR (quantitative polymerase chain reaction) for quick signal amplification and output. The method has strong selectivity and sensitivity for precise quantification, with a detection limit of 6 nmol L-1, i.e. 0.948 g L-1, which is far lower than the 5.0 g L-1 set by the United States Environmental Protection Agency, and it also operates well in retail rice samples.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Estados Unidos , Humanos , Cádmio , Técnicas Biossensoriais/métodos , Água
10.
Food Chem ; 424: 136374, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37207608

RESUMO

We developed a highly sensitive fluorescent assay to detect okadaic acid (OA), a prevalent aquatic toxin posing serious health risks. Our approach uses a mismatched duplexed aptamer (DA) immobilized on streptavidin-conjugated magnetic beads (SMBs) to create a DA@SMB complex. In the presence of OA, the cDNA unwinds, hybridizes with a G-rich segment pre-encoding circular template (CT), and undergoes rolling circle amplification (RCA) to produce G-quadruplexes, which are detected using the fluorescent dye thioflavine T (ThT). The method has a LOD of 3.1 × 10-3 ng/mL, a linear range of 0.1 âˆ¼ 1.0 × 103 ng/mL, and was successfully applied to shellfish samples with spiked recoveries of 85.9% ∼ 102.2% and RSD less than 13%. Furthermore, instrumental analysis confirmed the accuracy and reliability of this rapid detection method. Overall, this work represents a significant advancement in the field of rapid aquatic toxin detection and has important implications for public health and safety.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Ácidos Nucleicos , Ácido Okadáico , Reprodutibilidade dos Testes , Técnicas de Amplificação de Ácido Nucleico/métodos , Oligonucleotídeos , Corantes Fluorescentes , Técnicas Biossensoriais/métodos , Aptâmeros de Nucleotídeos/genética , Limite de Detecção
11.
Nucleic Acids Res ; 51(8): 3556-3572, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36938879

RESUMO

Thioflavin T (ThT) is a classical fluorescent dye gaining prominence in current research regarding nucleic acid conformations (NACs). However, most NACs with the ability to excite ThT fluorescent are unique or form in demanding conditions, limiting the extensiveness and depth of ThT application in sensing and imaging. Therefore, this study proposed CGG-AAA mismatched cavity hairpin ThT-light nucleic acid switches (CHTLNAS) with excellent fluorescence excitation over 500-fold higher than spontaneous, 17∼20-fold higher than ssDNA and 2.5∼5-fold higher than complementary duplex. Based on the excellent fluorescence excitation, convenient conformation formation, good sequence programmability, and flexible allosteric ability (known as the Worm-crack pod mechanism mediated by the target), it achieved the label- and enzyme-free detection of tetracycline (TET) and berberine (BB) at the pM level within 10 min. Moreover, it was found enable to realize the sensitive tracking of intracellular carriers at the nM level of ThT entry concentration, and prolongated its cell nuclear-entry time of ThT over 8 h, overcoming the non-specific high background signal interference of ThT in the nuclear region, and expanding the diversified application of ThT in cell biology research. Therefore, CHTLNAS is a more universal, practical tool than G-quadruplex or other kinds of NACs for ThT development and utilization in sensing and imaging platforms.


Assuntos
Técnicas Biossensoriais , Quadruplex G , Ácidos Nucleicos , Benzotiazóis , Corantes Fluorescentes , Técnicas Biossensoriais/métodos , Espectrometria de Fluorescência/métodos
12.
J Hazard Mater ; 447: 130798, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36669418

RESUMO

Although nucleic acid aptasensors are increasingly applied in the detection of environmentally hazardous biomolecules, several formidable challenges remain with this technique because of their vulnerability, high cost and suboptimal sensitivity. Here, a docking-aided rational tailoring (DART) strategy was established at three levels and in two dimensions for the refinement of malachite green (MG) DNA aptamers. Guided by in silico molecular docking, coarse and fine tailoring were conducted at three levels each, to significantly enhance fluorescence activation intensity and binding affinity in two dimensions. Empowered by the results of the rational tailoring, a mechanistic view of the MG DNA aptamer-target interaction was thoroughly analyzed via four types of interactions. To meet the demand for point-of-care testing (POCT), a label-free and ratiometric fluorescent aptasensor was developed leveraging the tailored MG aptamer, based on the binding site competition-equilibrium effect via the introduction of a reference dye. This sensitive, specific, low-cost and rapid aptasensor subsequently demonstrated outstanding detection performance, achieving an ideal signal response range of 5 nmol·L-1 - 6 µmol·L-1 and a low limit of detection (LOD) of 1.49 nmol·L-1. The DART strategy and systematic exploration of the MG DNA luminescent aptamers herein will provide a valuable reference in the field of aptamer tailoring, biosensing and bioimaging. The proposed label-free ratiometric aptasensor also provides a highly generalizable strategy for hazardous biomolecular detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Sistemas Automatizados de Assistência Junto ao Leito , Simulação de Acoplamento Molecular , Aptâmeros de Nucleotídeos/química , Corantes de Rosanilina , Hidrolases , Técnicas Biossensoriais/métodos , Limite de Detecção
13.
Hum Cell ; 36(1): 132-145, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36445533

RESUMO

The morbidity rate of ulcerative colitis (UC) in the world is increasing year by year, recurrent episodes of diarrhea, mucopurulent and bloody stools, and abdominal pain are the main symptoms, reducing the quality of life of the patient and affecting the productivity of the society. In this study, we sought to develop robust diagnostic biomarkers for UC, to uncover potential targets for anti-TNF-ɑ drugs, and to investigate their associated pathway mechanisms. We collected single-cell expression profile data from 9 UC or healthy samples and performed cell annotation and cell communication analysis. Revealing the possible pathogenesis of ulcerative colitis by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) analysis. Based on the disease-related modules obtained from weighted correlation network analysis (WGCNA) analysis, we used Lasso regression analysis and random forest algorithm to identify the genes with the greatest impact on disease (EPB41L3, HSD17B3, NDRG1, PDIA5, TRPV3) and further validated the diagnostic value of the model genes by various means. To further explore the relationship and mechanism between model genes and drug sensitivity, we collected gene expression profiles of 185 UC patients before receiving anti-tumor necrosis factor drugs, and we performed functional analysis based on the results of differential analysis between NR tissues and R tissues, and used single-sample GSEA (ssGSEA) and CIBERSORT algorithms to explore the important role of immune microenvironment on drug sensitivity. The results suggest that our model is not only helpful in aiding diagnosis, but also has implications for predicting drug efficacy; in addition, model genes may influence drug sensitivity by affecting immune cells. We suggest that this study has developed a diagnostic model with higher specificity and sensitivity, and also provides suggestions for clinical administration and drug efficacy prediction.


Assuntos
Colite Ulcerativa , Humanos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Qualidade de Vida , Inibidores do Fator de Necrose Tumoral , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas dos Microfilamentos/genética
14.
Small ; 19(6): e2205933, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36461678

RESUMO

The rapid, simple and low-cost preparation of DNA micro-nano-architectures remain challenging in biosensing and therapy. Polymerase chain reaction (PCR)-driven DNA micro-nano-flowers are used to construct a nanosized baicalin-compressed-aptamer-nanodrug (bcaND) via one-pot assembly for targeted and synergistic anti-obesity. In the design, the tailored Adipo-8 (tAdi-8) overhang in the PCR amplicon displays anti-obesity targeting activity, while the baicalin loaded in the bcaND by embedding the amplicon plays a three-fold role as a lipid-lowering factor, bcaND size compressor, and uncoupling protein-1 (UCP1)-raised thermogenic activator. The ingenious bcaND represents an advanced multifunctional nanomaterial capable of adjusting the morphology at an optimal 400/1 molar ratio of Mg2+ to phosphate groups, compressing the size from 2.699 µm to 214.76 nm using 1 mg/mL baicalin at a temperature of 70 °C, an effective payload with amplicons of up to 98.94%, and a maximum baicalin load of 86.21 g/g DNA. Responsive release in acidic conditions (pH 5.0) occurs within 72 h, accelerating thermogenesis via UCP1 up-regulation by 2.5-fold in 3T3-L1-preadipocytes and 13.7-fold in the white-adipose-tissue (WAT) of mice, targeting adipocytes and visceral white adipose tissue. It plays an efficient synergistic role in obesity therapy in vitro and in vivo, providing a new direction for DNA self-assembly nanotechnology.


Assuntos
Nanopartículas , Obesidade , Camundongos , Animais , Obesidade/tratamento farmacológico , Obesidade/genética , Adipócitos , Tecido Adiposo Branco/fisiologia , Nanopartículas/uso terapêutico , Camundongos Endogâmicos C57BL
17.
Front Chem ; 10: 856698, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386844

RESUMO

The use of pesticides is gradually increasing to improve the yield and quality of crops. However, excessive pesticide use has led to a dramatic pollution increase in the environment and agricultural products, posing severe human health risks. Therefore, rapid, sensitive pesticide detection is essential. Various pesticides detection methods and products have been developed in recent years. This brief review summarized the point-of-care testing (POCT) detection of pesticides based on multiple recognition, including protein-, aptamer-, nanomaterial-, and macrocycle-based recognition. The review aimed to address the growing demands for regulating and destroying pesticides or other adverse agriculture-related applications in the real world.

18.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35162990

RESUMO

Due to their hydrophilic, biocompatible and adjustability properties, hydrogels have received a lot of attention. The introduction of nucleic acids has made hydrogels highly stimuli-responsiveness and they have become a new generation of intelligent biomaterials. In this review, the development and utilization of smart nucleic acid hydrogels (NAHs) with a high stimulation responsiveness were elaborated systematically. We discussed NAHs with a high stimuli-responsiveness, including pure NAHs and hybrid NAHs. In particular, four stimulation factors of NAHs were described in details, including pH, ions, small molecular substances, and temperature. The research progress of nucleic acid hydrogels in biomedical applications in recent years is comprehensively discussed. Finally, the opportunities and challenges facing the future development of nucleic acid hydrogels are also discussed.


Assuntos
Hidrogéis/química , Ácidos Nucleicos/química , Concentração de Íons de Hidrogênio , Temperatura
19.
ACS Nano ; 16(1): 1036-1050, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34967620

RESUMO

The targeted delivery of phytochemicals that promote energy expenditure for obesity therapy remains a challenge. This study assembled a functionalized adipo-8 aptamer loaded with allicin using isothermal rolling-circle techniques to form a synergistic adipocyte-targeted binary-drug delivery system for treating obesity. The functionalized adipo-8 aptamer efficiently protected allicin from adsorption, showing significant potential to encapsulate, transport, and release molecular cargos into white adipose tissue. Introducing the negatively charged allicin, a phytochemical able to induce adipose tissue browning, reduced the diameters of DNA-nanoflower from 770 to 380 nm and increased cellular uptake efficiency up to 118.7%. The intracellular distribution observed via confocal microscopy confirmed the successful receptor recognition mediated by aptamers in the DNA-nanoflower-allicin (NFA) framework as well as its excellent stability to escape from lysosomes. In vivo results demonstrated that subcutaneous administration of NFA effectively promoted adipocyte browning and systematic energy expenditure with minimal side effects. Furthermore, the G-quadruplex in the mitochondrial uncoupling protein-1 promoter was found to be an interactive allicin target for regulating thermogenesis to combat obesity.


Assuntos
Tecido Adiposo Branco , Termogênese , Humanos , Obesidade/tratamento farmacológico , Metabolismo Energético , Sistemas de Liberação de Medicamentos , Tecido Adiposo Marrom
20.
J Hazard Mater ; 425: 127976, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34883379

RESUMO

The complicated labeling procedure and high cost of split aptasensors have hitherto limited their application in the detection of hazardous substances. Herein we report the first examples of label-free aptasensors based on the fusion of a binary split G-quadruplex and malachite green (MG) aptamer, transducing recognition events into fluorescent signals through the allosteric regulation of the aptamer to achieve selective and sensitive detection. Specifically, RNA MGA was successfully converted into DNA MGA with comparable affinity and improved stability, thereby overcoming the limitations of poor stability and high expense. We subsequently split the DNA MGA and attached them to a G-rich DNA sequence at the 5' and 3' ends, to construct the binary split allosteric aptasensor. The performance of the binary split aptasensor for MG detection was significantly improved based on proposed allosteric regulation strategy, and the reconfiguration capability of the aptamers upon binding with targets was proven, providing the binary split aptasensor with superior sensitivity and selectivity. This sensing method has a wide dynamic detection range of 5 nmol·L-1 to 500 µmol·L-1, with a low limit of detection (LOD) of 4.17 nmol·L-1, and achieves the ultra-sensitive and super-rapid detection of MG. This newly proposed aptasensor is equipped with the advantages of being label-free, time saving and economical. More importantly, this successful construction of a fused aptasensor expands the principles of split aptasensor design and provides a universal platform for the detection of environmental contaminants.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Quadruplex G , Limite de Detecção , Corantes de Rosanilina
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