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1.
Opt Lett ; 49(11): 3138-3141, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824347

RESUMO

Visible light communication (VLC) technology with rich spectrum resources is thought of as an essential component in the future ubiquitous communication networks. Accurately monitoring its transmission impairments is important for improving the stability of high-speed communication networks. Existing research on intelligently monitoring the signal-to-noise ratio (SNR) performance of VLC focuses primarily on the application of neural networks but neglects the physical nature of communication systems. In this work, we propose an intelligent SNR estimation scheme for VLC systems, which is based on the symmetry of constellation diagrams with classical deep learning frameworks. In order to increase the accuracy of the SNR estimation scheme, we introduce two data augmentation methods (DA): point normalization and quadrant normalization. The results of extensive simulations demonstrate that the proposed point normalization method is capable of improving accuracy by about 5, 10, 14, and 26%, respectively, for 16-, 64-, 256-, and 1024-quadrature amplitude modulation compared with the same network frameworks without DA. The effect of accuracy improvement can be further superimposed with traditional DA methods. Additionally, the extensive number of constellation points (e.g., 32, 64, 128, 256, 512, 1024, and 2048) on the accuracy of SNR estimation is also investigated.

2.
Pharmacol Res ; 192: 106798, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37211240

RESUMO

Exosomes, small extracellular vesicles that function as a key regulator of cell-to-cell communication, are emerging as a promising candidate for bone regeneration. Here, we aimed to investigate the effect of exosomes from pre-differentiated human alveolar bone-derived bone marrow mesenchymal stromal cells (AB-BMSCs) carrying specific microRNAs on bone regeneration. Exosomes secreted from AB-BMSCs pre-differentiated for 0 and 7 days were cocultured with BMSCs in vitro to investigate their effect on the differentiation of the BMSCs. MiRNAs from AB-BMSCs at different stages of osteogenic differentiation were analyzed. BMSCs seeded on poly-L-lactic acid(PLLA) scaffolds were treated with miRNA antagonist-decorated exosomes to verify their effect on new bone regeneration. Exosomes pre-differentiated for 7 days effectively promoted the differentiation of BMSCs. Bioinformatic analysis revealed that miRNAs within the exosomes were differentially expressed, including the upregulation of osteogenic miRNAs (miR-3182, miR-1468) and downregulation of anti-osteogenic miRNAs (miR-182-5p, miR-335-3p, miR-382-5p), causing activation of the PI3K/Akt signaling pathway. The treatment of BMSC-seeded scaffolds with anti-miR-182-5p decorated exosomes demonstrated enhanced osteogenic differentiation and efficient formation of new bone. In conclusion, Osteogenic exosomes secreted from pre-differentiated AB-BMSCs were identified and the gene modification of exosomes provides great potential as a bone regeneration strategy. DATA AVAILABILITY STATEMENT: Data generated or analyzed in this paper partly are available in the GEO public data repository(http://www.ncbi.nlm.nih.gov/geo).


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Humanos , Osteogênese , Exossomos/genética , Exossomos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regeneração Óssea/genética , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular
3.
J Adv Nurs ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37921103

RESUMO

OBJECTIVE: To explore the possible barriers and facilitators to implementing the Upright Positions in the Second Stage of Labour (UPSSL) programme in Chinese healthcare settings. DESIGN: A mixed-method convergent design with the guidance of Consolidated Framework for Implementation Research (CFIR). METHODS: An online survey study and semi-structured interviews were conducted between March and May 2023. Healthcare professionals were recruited from four hospitals in Shijiazhuang, China. One hundred and thirty-one participants completed the survey study, and 23 of them were interviewed individually. Descriptive statistics evaluated the possible barriers and facilitators of implementing the UPSSL programme within the CFIR framework quantitatively. Guided by the CFIR framework, qualitative data were analysed using directed content analysis to summarize healthcare professionals' perspectives on barriers and facilitators of the UPSSL programme. RESULTS: Multiple intersectional barriers and facilitators were identified from the survey and semi-interviews. Healthcare professionals believed that the UPSSL programme has a scientific evidence base, systematic contents, and possible benefits for women. However, various barriers existed at individual, system, and organizational levels. Major barriers included healthcare professionals and women's safety concerns towards the use of upright positions during childbirth, the healthcare professionals' unfamiliarity with assisting an upright position birth, poor adaptability of the programme protocol, inadequate facilities and staffing, and a lack of readiness to change in the clinical setting. CONCLUSIONS: To facilitate the implementation of the UPSSL programme in China, tailored antenatal education on upright positions, especially addressing safety-related issues, should be provided to pregnant women, their families, or peers to enhance their understanding of and familiarity with such positions. Healthcare professionals should also be offered adequate training opportunities and necessary facilities. Furthermore, national-level policy changes might be required to address midwifery workforce shortages. Additionally, further research is warranted to select, adapt, and test effective implementation strategies for programme adoption. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: What problem did the study address? The adoption of upright positions during the second stage of labour could promote better maternal and neonatal outcomes and a positive childbirth experience. However, the adoption of upright positions during the second stage of labour is suboptimal in healthcare settings in China. Barriers and facilitators of implementing upright positions during childbirth are unclear. What were the main findings? A range of barriers and facilitators within the CFIR framework to promote upright positions during childbirth from healthcare professionals' perspectives were identified, and the major barriers included safety concerns towards and unfamiliarity with an upright position birth, inadequate facilities and staffing, and a lack of readiness to change in the clinical setting. Where and on whom will the research have an impact? This study will enable a better understanding of the barriers and facilitators to promoting upright positions in the second stage of labour in China. The smooth and effective implementation of the UPSSL programme could help to promote better maternal and neonatal outcomes and improve women's childbirth experiences. REPORTING METHOD: The reporting of this study followed the Consolidated Criteria for Reporting Qualitative Research (COREQ) and Good Reporting of A Mixed Methods Study (GRAMMS) guidelines. PATIENT OR PUBLIC CONTRIBUTION: In this study, healthcare professionals were involved in refining the topic guides and survey questions. Additionally, findings from the interviews were returned to them for comments and corrections.

4.
Sensors (Basel) ; 23(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37430853

RESUMO

Wearable surface electromyography (sEMG) signal-acquisition devices have considerable potential for medical applications. Signals obtained from sEMG armbands can be used to identify a person's intentions using machine learning. However, the performance and recognition capabilities of commercially available sEMG armbands are generally limited. This paper presents the design of a wireless high-performance sEMG armband (hereinafter referred to as the α Armband), which has 16 channels and a 16-bit analog-to-digital converter and can reach 2000 samples per second per channel (adjustable) with a bandwidth of 0.1-20 kHz (adjustable). The α Armband can configure parameters and interact with sEMG data through low-power Bluetooth. We collected sEMG data from the forearms of 30 subjects using the α Armband and extracted three different image samples from the time-frequency domain for training and testing convolutional neural networks. The average recognition accuracy for 10 hand gestures was as high as 98.6%, indicating that the α Armband is highly practical and robust, with excellent development potential.


Assuntos
Antebraço , Gestos , Humanos , Eletromiografia , Intenção , Aprendizado de Máquina
5.
Sensors (Basel) ; 23(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36992010

RESUMO

The inspection of railway fasteners to assess their clamping force can be used to evaluate the looseness of the fasteners and improve railway safety. Although there are various methods for inspecting railway fasteners, there is still a need for non-contact, fast inspection without installing additional devices on fasteners. In this study, a system that uses digital fringe projection technology to measure the 3D topography of the fastener was developed. This system inspects the looseness through a series of algorithms, including point cloud denoising, coarse registration based on fast point feature histograms (FPFH) features, fine registration based on the iterative closest point (ICP) algorithm, specific region selection, kernel density estimation, and ridge regression. Unlike the previous inspection technology, which can only measure the geometric parameters of fasteners to characterize the tightness, this system can directly estimate the tightening torque and the bolt clamping force. Experiments on WJ-8 fasteners showed a root mean square error of 9.272 N·m and 1.94 kN for the tightening torque and clamping force, demonstrating that the system is sufficiently precise to replace manual measurement and can substantially improve inspection efficiency while evaluating railway fastener looseness.

6.
Int J Mol Sci ; 24(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37958715

RESUMO

Persimmon is a fruit that contains sugars, vitamins, phenolic compounds, and various other nutrients. The aim of this study was to explore the structure of carboxymethylated persimmon polysaccharide (CM-PFP) and its interaction with the human gut microbiota. Carboxymethyl modification of the persimmon polysaccharide (PFP) increased both the Mw and Mn, enhanced dispersion stability, and decreased thermal stability. Both PFP and CM-PFP promoted the proliferation of Lactobacillus while inhibiting the proliferation of Staphylococcus aureus and Escherichia coli. In the simulated fecal fermentation, the pH of PFP- and CM-PFP-containing media decreased, the content of short-chain fatty acids increased, and the abundance of intestinal flora at the phylum and genus levels changed. The relative abundance of harmful intestinal bacteria was significantly reduced in both PFP and CM-PFP groups. Furthermore, it was found that CM-PFP was more easily metabolized than PFP, glucose, and fructo-oligosaccharide (FOS) and had a proliferation increase effect on Lactobacillus. Therefore, CM-PFP has a significant positive effect on both Lactobacillus proliferation and the human gut microbiota.


Assuntos
Diospyros , Microbioma Gastrointestinal , Humanos , Frutas/química , Diospyros/química , Polissacarídeos/química , Proliferação de Células
7.
Z Geburtshilfe Neonatol ; 227(1): 24-30, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36368685

RESUMO

BACKGROUND: Probiotic supplements may have some potential in preventing gestational diabetes, and this meta-analysis aims to explore the efficacy of probiotic supplements to prevent gestational diabetes. METHODS: PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systematically searched, and we included randomized controlled trials (RCTs) assessing the effect of probiotic supplements on the incidence of gestational diabetes mellitus. Meta-analysis was performed using the fixed-effect or random-effect model as appropriate. RESULTS: Six RCTs were finally included in the meta-analysis. Overall, compared with control intervention in pregnant women, probiotic supplementation intervention showed no obvious impact on the incidence of gestational diabetes (OR=0.68; 95% CI=0.39 to 1.20; P=0.18), fasting plasma glucose (SMD=-0.05; 95% CI=-0.29 to 0.19; P=0.69), 2 h-OGTT (SMD=-0.07; 95% CI=-0.27 to 0.13; P=0.47), gestational age (SMD=0.04; 95% CI=-0.14 to 0.21; P=0.69) or preeclampsia (OR=1.22; 95% CI=0.83 to 1.78; P=0.31). CONCLUSIONS: Probiotic supplementation was confirmed to have no benefits for the prevention of gestational diabetes.


Assuntos
Diabetes Gestacional , Probióticos , Feminino , Humanos , Gravidez , Diabetes Gestacional/prevenção & controle , Diabetes Gestacional/epidemiologia , Suplementos Nutricionais , Idade Gestacional , Probióticos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4731-4737, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37802812

RESUMO

This study aimed to analyze the effect of matrine on tumor necrosis factor-α(TNF-α)-induced inflammatory response in human umbilical vein endothelial cells(HUVECs) and explore whether the underlying mechanism was related to the miR-25-3p-mediated Krüppel-like factor 4(Klf4) pathway. The HUVEC cell inflammation model was induced by TNF-α stimulation. After 24 or 48 hours of incubation with different concentrations of matrine(0.625, 1.25, and 2.5 mmol·L~(-1)), CCK-8 assay was used to detect cell proliferation. After treatment with 2.5 mmol·L~(-1) matrine for 48 h, the expression of TNF-α, interleukin-6(IL-6), interleukin-1ß(IL-1ß), and Klf4 mRNA and miR-25-3p was detected by real-time fluorescence-based quantitative PCR, and the protein expression of TNF-α, IL-6, IL-1ß, and Klf4 was detected by Western blot. The anti-miR-25-3p was transfected into HUVECs, and the effect of anti-miR-25-3p on TNF-α-induced cell proliferation and inflammatory factors was detected by the above method. The cells were further transfected with miR-25-3p and incubated with matrine to detect the changes in proliferation and expression of related inflammatory factors, miR-25-3p, and Klf4. The targeting relationship between miR-25-3p and Klf4 was verified by bioinformatics analysis and dual luciferase reporter gene assay. The results displayed that matrine could inhibit TNF-α-induced HUVEC proliferation, decrease the mRNA and protein expression of TNF-α, IL-6, and IL-1ß, increase the mRNA and protein expression of Klf4, and reduce the expression of miR-25-3p. Bioinformatics analysis showed that there were specific complementary binding sites between miR-25-3p and Klf4 sequences. Dual luciferase reporter gene assay confirmed that miR-25-3p negatively regulated Klf4 expression in HUVECs by targeting. The inhibition of miR-25-3p expression can reduce TNF-α-induced cell proliferation and mRNA and protein expression of TNF-α, IL-6, and IL-1ß. MiR-25-3p overexpression could reverse the effect of matrine on TNF-α-induced cell proliferation and the mRNA and protein expression of TNF-α, IL-6, IL-1ß, and Klf4. This study shows that matrine inhibits the inflammatory response induced by TNF-α in HUVECs through miR-25-3p-mediated Klf4 pathway.


Assuntos
MicroRNAs , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células Endoteliais da Veia Umbilical Humana , Matrinas , Interleucina-6/genética , Transdução de Sinais , Antagomirs , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/metabolismo , Luciferases/metabolismo , Luciferases/farmacologia , RNA Mensageiro , Apoptose
9.
Anal Bioanal Chem ; 414(23): 6753-6760, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35909164

RESUMO

Nanomaterial-derived quantum dots (QDs) are excellent electrochemiluminescence (ECL) luminophores and play an important role in optical sensing due to their excellent water solubility, good biocompatibility and tunable molecular size. In this work, a novel strategy was designed to form nano-hybrid Ti3C2 QDs-AuNPs in situ as a luminophore based on the unique reducibility of Ti3C2 QDs, which showed remarkable and stable ECL performance. Here, AuNPs were formed in situ without the addition of reducing agents and stabilizers, leading to threefold enhancement of the ECL signal of Ti3C2 QDs due to their excellent charge transfer capability. Meanwhile, Ti3C2 QDs-AuNPs with abundant Ti atoms also acted as recognition units. Through skillful combination with hybridization chain reaction (HCR) to expose more phosphate, an ECL platform was constructed to detect polynucleotide kinase (PNK) with good specificity and sensitivity. A lower limit of detection limit of 2.7×10-5 U mL-1 was achieved, with a wide linear relationship ranging from 0.0001 to 10 U mL-1. This novel strategy provides a guide for the application of nano-hybrid Ti3C2 QDs-AuNPs as a luminophore in the field of ECL bioanalysis. Novel in situ-formed nano-hybrid Ti3C2 QDs-AuNPs were prepared as a luminophore, with threefold enhancement of the ECL signal of Ti3C2 QDs.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Pontos Quânticos , Técnicas Eletroquímicas , Ouro , Medições Luminescentes , Titânio
10.
Anal Bioanal Chem ; 414(29-30): 8309-8315, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36239751

RESUMO

Electrochemiluminescence (ECL) of luminol is a well-established methodology in analytical chemistry and bioimaging. Developing novel strategies to enhance the ECL signal of this model emitter is a challenging but rewarding task. In this work, we introduced the high-intensity focused ultrasound (HIFU), as a pretreatment means and a non-invasive way to trigger and boost the ECL signal with a 40-fold significant enhancement in the luminol-O2 system without the addition of exogenous co-reactants. The superoxide anion (O2-•) generated in situ by HIFU was the key initiator for boosting the ECL emission as demonstrated in this study for the first time. This promising co-reactant-free strategy could find potential applications for ultrasensitive ECL detection in the analysis of complex biological entities.


Assuntos
Técnicas Biossensoriais , Luminol , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Limite de Detecção
11.
Neuroradiology ; 64(4): 817-824, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35079864

RESUMO

PURPOSE: The aim of this study was to explore elderly patients with end-stage renal disease (ESRD) white matter changes, the relationship between white matter (WM) abnormalities and emotional regulation strategies, coping styles in elderly ESRD patients. METHODS: Twenty-eight elderly ESRD patients and twenty-eight sex and age matched healthy controls (HC) were included in this study. Tract-based spatial statistic (TBSS) was used to investigate the microstructural changes of WM. Two questionnaires were used to measure emotional regulation strategies and coping styles. RESULTS: Neuroimaging analysis showed that the damage of WM structure was widespread in elderly ESRD patients. Psychological test results showed that there were differences in emotional regulation strategies and coping styles between elderly ESRD patients and HC. Furthermore, mediating analysis showed that the mean diffusivity (MD) of the significantly different brain regions played a complete mediating role between group and positive coping style. CONCLUSION: These results suggest that the integrity of WM, emotional regulation strategies and coping styles play an important role in ESRD patients. Our findings provide evidence that positive coping style may be fully mediated by MD. These results may help us develop new ways to treat and prevent physical and psychological problems in elderly ESRD hemodialysis patients.


Assuntos
Adaptação Psicológica , Falência Renal Crônica , Substância Branca , Idoso , Estudos de Casos e Controles , Humanos , Falência Renal Crônica/psicologia , Falência Renal Crônica/terapia , Diálise Renal , Inquéritos e Questionários , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
12.
Sensors (Basel) ; 22(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35808541

RESUMO

The ultrasonic Lamb wave detection principle can realize the noncontact measurement of liquid level in closed containers. When designing an ultrasonic Lamb wave sensor, it is vital to thoroughly study and select the optimal wedge size at the front of the sensor. In this paper, firstly, we select the best working mode of Lamb waves according to their propagation dispersion curve in aluminum alloy, and we obtain the best angle of wedge through experiments. Secondly, we study the impact of the size of the wedge block on the results, and we obtain the selection method of wedge block parameters. The evaluations show that, when the frequency-thickness product is 3 MHz·mm, the Lamb waves work in the A1 mode, and the experimental effect is the best. At this time, the incident angle of the ultrasonic wave is 27.39°. The wedge thickness should be designed to avoid the near-field area of the ultrasonic field, and we should choose the length as odd multiples of 1/4 wavelength. The rules obtained from the experiment can effectively select the best working mode for ultrasonic Lamb waves, while also providing a basis for the design of the wedge block size in a Lamb wave sensor.

13.
J Obstet Gynaecol ; 42(7): 2833-2839, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35980753

RESUMO

The aim of this study was to investigate the potential of pregnancy-associated plasma protein A (PAPP-A) and clinical data in predicting gestational diabetes mellitus (GDM). Clinical data of 318 pregnant women with GDM and 200 healthy pregnant women were retrospectively analysed. The age, BMI and caesarean section in GDM were significantly higher than in normal group. Serum and placental levels of PAPP-A were significantly lower in GDM than in normal group. Pearson's correlation analysis showed that serum levels of PAPP-A were negatively correlated with BMI and blood glucose level. Binary logistic regression analysis displayed that PAPP-A were the potential factors influencing GDM. The area under the ROC curve (AUC) for PAPP-A combined with BMI in predicting GDM was 0.941, significantly higher than that of the single one. The potential of PAPP-A in the first trimester is limited in predicting GDM. PAPP-A combined with BMI is highly conductive for predicting GDM.Impact statementWhat is already known on this subject? GDM not only increases the risk of perinatal morbidity, but also results in an increased risk of long-term sequelae for both mother and child including diabetes, cardiovascular disease obesity. Previous data indicate that besides glycemic control in the second trimester, interventions initiated early in pregnancy can reduce the rate of GDM in pregnant women. The expression of PAPP-A in serum of GDM pregnant women was decreased in the first trimester. Whereas, whether PAPP-A can be as an early predictor of GDM is not clear.What do the results of this study add? The present study shows that PAPP-A MoM was less than 0.6757 in the first trimester of pregnancy is more prone to GDM. The potential of PAPP-A in the first trimester is limited in predicting GDM. PAPP-A combined with BMI is highly conductive for predicting GDM.What are the implications of these findings for clinical practice and/or further research? Early GDM prediction is crucial for prevention and management of GDM, to cope with the rising prevalence of GDM and reduce later life chronic disease of both mother and child. Based on the level of PAPP-A MoM and BMI, interventions such as lifestyle changes initiated early in pregnancy shouldbeenabledin pregnant women.


Assuntos
Índice de Massa Corporal , Diabetes Gestacional , Proteína Plasmática A Associada à Gravidez , Feminino , Humanos , Gravidez , Cesárea , Diabetes Gestacional/diagnóstico , Placenta/metabolismo , Primeiro Trimestre da Gravidez , Proteína Plasmática A Associada à Gravidez/análise , Prognóstico , Estudos Retrospectivos
14.
J Nurs Manag ; 30(7): 3608-3617, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36121431

RESUMO

AIMS: This study aimed to develop a Practice Programme for Upright Positions in the Second Stage of Labour to provide a reference for midwifery professionals in the standardized implementation of upright positions in clinical practice. BACKGROUND: The adoption of upright positions in the second stage of labour is recommended by many international organizations, but upright positions have not been widely used and their implementation varies greatly across studies. METHODS: The Practice Programme for Upright Positions in the Second Stage of Labour was developed under the guidance of the Medical Research Council framework for developing and evaluating complex interventions and the World Health Organization handbook for guideline development. Four stages were conducted: (1) establishing the intervention development group, (2) identifying a theoretical basis and forming a content framework, (3) evidence retrieval and synthesis and (4) refining and modelling the practice programme. RESULTS: The content framework of the Practice Programme for Upright Positions in the Second Stage of Labour was formed based on the literature review, semi-structured interviews and expert consultation, including indications and contraindications, implementation methods, observations, potential risks and precautions. According to each item, we conducted a series of systematic reviews, and summarized the available best evidence from clinical guidelines, systematic reviews and original studies. Eventually, the Practice Programme for Upright Positions in the Second Stage of Labour was developed, integrating the findings of the iterative evidence reviews and revised by stakeholders. CONCLUSIONS: This study first reported the development process of the Practice Programme for Upright Positions in the Second Stage of Labour, characterized by evidence-based, iteratively processed and highly rigorous. The implications may guide researchers to embed the intervention normatively into clinical practice for improving maternal and infant outcomes. IMPLICATIONS FOR NURSING MANAGEMENT: The Practice Programme for Upright Positions in the Second Stage of Labour could facilitatesystematic management of labour positions and guide midwives in the successful implementation of upright positions.


Assuntos
Pesquisa Biomédica , Segunda Fase do Trabalho de Parto , Gravidez , Feminino , Humanos , Posicionamento do Paciente , Postura , Revisões Sistemáticas como Assunto
15.
Anal Bioanal Chem ; 413(28): 6963-6971, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34581826

RESUMO

An efficient electrogenerated chemiluminescence (ECL) nanoprobe (luminol-Au NPs-Ti3C2) was constructed based on Ti3C2Tx MXene (Ti3C2)-mediated in situ formation of Au NPs and anchoring luminol to fabricate a sensitive ECL biosensor for miRNA-155 detection. Herein, Ti3C2 with rich Ti vacancy defects was used as reducing agent, and Au NPs were generated in situ and anchored on the Ti3C2 (Au NPs-Ti3C2). Moreover, the Au NPs-Ti3C2 composites were used as a carrier and provided a large number of sites for the efficient linking of luminol through Au-N bonds to form stable luminol-Au NPs-Ti3C2. The immobilization of ECL emitters is a versatile strategy which not only shortens the electron transmission distance between luminol and electrode, but also provides naked catalytic predominated (111) facets of Au NPs with high electrocatalytic activity, significantly improving the ECL signal of luminol. Furthermore, a catalytic hairpin assembly (CHA) reaction was used, resulting in further amplification of the signal. As a result, the as-prepared ECL biosensor exhibited a linear range from 0.3 fM to 1 nM with a detection limit of 0.15 fM, and demonstrated high reliability of miRNA-155 detection even in human serum samples. The construction of a multifunctional ECL probe with excellent ECL emission opens a new chapter for the application of Ti3C2 in the field of bioanalysis. Herein, Au NPs were generated in situ and anchored on the Ti3C2 (Au NPs-Ti3C2). Moreover, the Au NPs-Ti3C2 was used as a carrier and linked luminol through Au-N bonds to form a stable luminol-Au NPs-Ti3C2 nanoprobe. The strategy displayed versatility which not only shortened the electron transmission distance between luminol and the electrode, but also provided a catalytic surface with high electrocatalytic activity of Au NPs that significantly improved the ECL signal of luminol.


Assuntos
Ouro/química , Luminescência , Luminol/química , Nanopartículas Metálicas/química , MicroRNAs/sangue , Sondas RNA/química , Titânio/química , Técnicas Biossensoriais/métodos , Eletroforese em Gel de Poliacrilamida , Humanos , Reprodutibilidade dos Testes , Análise Espectral/métodos
16.
Phys Chem Chem Phys ; 23(14): 8500-8507, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33876013

RESUMO

The electrochemical switching ion exchange (ESIX) technique has been widely used for the separation and recovery of radioactive cesium ions (Cs+) from wastewater. In this study, a series of BiOX (X = F, Cl, Br, I) materials were first evaluated for their absorption properties to Cs+ through density functional theory (DFT) calculations. The calculations predict that BiOBr has the best absorption performance among the four materials, BiOF, BiOCl, BiOBr, and BiOI, due to its high absorption energy and low ion migration energy barrier to Cs+. Simultaneously, the selectivity calculations revealed that BiOBr also showed the best selectivity for Cs+ compared with Li+ and Na+. Subsequently, four materials were prepared using the hydrothermal synthesis method and their electrochemical absorption performance was tested. The results showed that BiOBr has the highest electroactivity, and its absorption capacity was up to 16 mg Cs+/g BiOBr in a solution mixture of 50 ppm Li+, Na+, and Cs+. Based on our theoretical calculations and experiments, our findings provide prospective insights for predicting the electrochemical absorption performance of materials using first-principles calculations.

17.
Med Sci Monit ; 27: e931473, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385410

RESUMO

BACKGROUND Cryoablation of hepatocellular carcinoma (HCC) close to major organs or viscus is challenging because it can cause complications. This retrospective study aimed to investigate the safety and efficacy of percutaneous argon-helium cryoablation of small HCC located adjacent to major organs or viscus. MATERIAL AND METHODS Ninety-two patients who underwent percutaneous argon-helium cryoablation between February 2012 and December 2018 at the Fifth Medical Center of the Chinese People's Liberation Army General Hospital were included. Treatment efficacy was evaluated by magnetic resonance imaging or triphasic computed tomography scan within 1 week after each cryoablation procedure. Local tumor progression, distant recurrence, and overall survival were analyzed using the Kaplan-Meier method and log-rank test. RESULTS A total of 92 patients with small HCC located adjacent to major organs or viscus who underwent cryoablation were retrospectively reviewed. The number of patients with tumors adjacent to the gallbladder, portal or hepatic vein, diaphragm, stomach, heart, and intestine was 22, 1, 39, 6, 8, and 16, respectively. Cumulative local tumor progression rates at 1 and 2 years were 2.8% and 7.3%, respectively. Cumulative distant recurrence rates at 1, 2, and 3 years were 11.1%, 17.6%, and 20.7%, respectively. The overall survival rates at 1, 2, and 4 years were 100%, 93.6%, and 74.9%, respectively. Major complications were observed in 5 (5.4%) patients. Minor complications were observed in 85 (92.4%) patients. CONCLUSIONS This experience from a single center showed that percutaneous argon-helium cryoablation was safe and effective in the management of small HCC that is located adjacent to major organs or viscus.


Assuntos
Carcinoma Hepatocelular/cirurgia , Criocirurgia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Argônio/administração & dosagem , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Criocirurgia/métodos , Hélio/administração & dosagem , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Órgãos em Risco , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento
18.
J Obstet Gynaecol Res ; 47(6): 2225-2229, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33719103

RESUMO

Here we report an extremely rare case of immature congenital orbital teratoma. The ultrasound scan at the 28+1 week of gestation revealed a massive, solid, and cystic mass in the left orbital region of the fetus. The lesion site was confirmed by magnetic resonance imaging. Based on clinical examination and imaging, the diagnosis of orbital teratoma without intracranial extension was made. Histopathological examination further confirmed the diagnosis of immature teratoma. The clinical course, radiographic, and histopathological findings of this disease were also summarized.


Assuntos
Teratoma , Feminino , Feto , Humanos , Imageamento por Ressonância Magnética , Gravidez , Diagnóstico Pré-Natal , Teratoma/diagnóstico por imagem , Teratoma/cirurgia , Ultrassonografia
19.
Anal Chem ; 92(15): 10668-10676, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32600031

RESUMO

Herein, a novel electrogenerated chemiluminescence (ECL) method for highly sensitive kinase activity and inhibitors screening was developed based on graphitic carbon nitride nanosheet (g-C3N4) nanoparticle embellished titanium carbide (Ti3C2) MXene nanosheets, integrating the highly efficient recognition and signal amplification activity. In this strategy, kemptide was first immobilized onto a gold electrode, and it was phosphorylated by the protein kinase A which was used as a model. The g-C3N4-MXene probe can adsorb explicitly onto the electrode based on chelation between the phosphate group and Ti defect sites enriched in MXenes. Besides the abundant active sites on MXene for the highly efficient binding with phosphate groups, the Ti3C2 MXene not only provides a unique conductive platform to accommodate more g-C3N4 nanoparticles but also facilitates the electron transfer on the electrode interface and suppresses the passivation of g-C3N4 that explores their highly efficient ECL emission with high stability. The obtained ECL signals were closely related to the kinase activity and can be applied for protein kinase A (PKA) activity detection. Under the optimal conditions, the proposed ECL biosensor provided a quantitative readout to PKA concentration in the range 0.015-40 U mL-1 with the detection limit of 1.0 mU mL-1. The ECL biosensor was also successfully applied to monitor drug-triggered kinase activation and quantitative analysis of the kinase inhibitors in MCF-7 cell lysates. This work shows that the proposed ECL biosensor has the potential to be a powerful tool for PKA study and clinical diagnostics as well as the discovery of new targeted drugs.


Assuntos
Técnicas Biossensoriais/métodos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ensaios Enzimáticos/métodos , Medições Luminescentes , Nanopartículas/química , Nitrilas/química , Titânio/química , Eletroquímica , Humanos , Células MCF-7 , Modelos Moleculares , Conformação Molecular
20.
Anal Chem ; 92(7): 5546-5553, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32186362

RESUMO

In this work, an ultrasensitive electrogenerated chemiluminescence (ECL) biosensor for exosomes and their surface proteins was developed by the in situ formation of gold nanoparticles (AuNPs) decorated Ti3C2 MXenes hybrid with aptamer modification (AuNPs-MXenes-Apt). In this strategy, the exosomes were efficiently captured on an exosome recognized CD63 aptamer modified electrode interface. Meanwhile, in situ formation of gold nanoparticles on single layer Ti3C2MXenes with aptamer (MXenes-Apt) modification was obtained, in which MXenes acted as both reductants and stabilizer, and no additional reductant and stabilizer involved. The in situ formed AuNPs-MXenes-Apt hybrid not only presented highly efficient recognition of exosomes specifically, but also provide naked catalytic surface with high electrocatalytic activity of gold nanoparticles with predominated (111) facets that significantly improved the ECL signal of luminol. In this way, a highly sensitive ECL biosensor for exosomes detection was constructed ascribing to the synergistic effects of large surface area, excellent conductivity, and catalytic effects of the AuNPs-MXenes-Apt. The detection limit is 30 particles µL-1 for exosomes derived from HeLa cell line, which was over 1000 times lower than that of conventional ELISA method and the linear range was from 102 particles µL-1 to 105 particles µL-1. This ECL sensing platform possessed high selectivity toward exosomes and their surface proteins derived different kinds of tumor cell lines (HeLa cells, OVCAR cells and HepG2 cells), and enabled sensitive and accurate detection of exosomes from human serum, which implied that the ECL biosensor provided a feasible, sensitive, and reliable tool for exosomes detection in exosomes-related clinical diagnostic.


Assuntos
Técnicas Biossensoriais/métodos , Exossomos/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Proteínas/metabolismo , Titânio/química , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Eletroquímica , Células HeLa , Células Hep G2 , Humanos , Limite de Detecção , Medições Luminescentes , Modelos Moleculares , Conformação Molecular
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