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1.
Anal Chem ; 96(13): 5251-5257, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38512289

RESUMO

The electrochemiluminescence (ECL) intensity can be regulated by ionic current passing through the microchannel, which broadened the regulation of the ECL sensors. But in the early reported sensors, the electrostatic repulsion and steric hindrance caused few targets to approach the interface of the microchannel driven by concentration difference, which reduced the detection efficiency and prolonged the detection period. In this study, different accumulation strategies, such as a positive electric field and different polarity electric fields, were designed to accumulate targets in the microchannel. The interaction of azide groups and hydrogen sulfide served as a research model. Hydrogen sulfide can react with the negatively charged azide groups in the microchannel surface to produce positively charged amino groups, decreasing the negative charge density of the microchannel and thus altering the ionic current and ECL intensity. The accumulation of hydrogen sulfide at the microchannel tip can increase the collision probability with azide groups to improve the detection efficiency, and the integration of accumulation and reaction can shorten the detection period to 28 min. The hydrogen sulfide concentration on the microchannel tip accumulated by applying different polarity electric fields was 22.3-fold higher than that accumulated by applying a positive electric field. The selected research model broadened the application range of a microchannel-based ECL sensor and confirmed the universality of the microchannel-based ECL sensor.

2.
Anal Chem ; 96(10): 4290-4298, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38427621

RESUMO

Halide perovskites have emerged as a highly promising class of photoelectric materials. However, the application of lead-based perovskites has been hindered by their toxicity and relatively weak stability. In this work, a composite material comprising a lead-free perovskite cesium copper iodide (CsCu2I3) nanocrystal and a metal-organic framework (MOF-801) has been synthesized through an in situ growth approach. The resulting composite material, denoted as CsCu2I3/MOF-801, demonstrates outstanding stability and exceptional optoelectronic characteristics. MOF-801 may serve a dual role by acting as a protective barrier between CsCu2I3 nanocrystals and the external environment, as well as promoting the efficient transfer of photogenerated charge carriers, thereby mitigating their recombination. Consequently, CsCu2I3/MOF-801 demonstrates its utility by providing both stability and a notably high initial photocurrent. Leveraging the inherent reactivity between H2S and the composite material, which results in the formation of Cu2S and structural alteration, an exceptionally sensitive photoelectrochemical sensor for H2S detection has been designed. This sensor exhibits a linear detection range spanning from 0.005 to 100 µM with a remarkable detection limit of 1.67 nM, rendering it highly suitable for precise quantification of H2S in rat brains. This eco-friendly sensor significantly broadens the application horizon of perovskite materials and lays a robust foundation for their future commercialization.

3.
BMC Microbiol ; 24(1): 195, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849736

RESUMO

BACKGROUND: Rhizosphere and endophytic fungi play important roles in plant health and crop productivity. However, their community dynamics during the continuous cropping of Knoxia valerianoides have rarely been reported. K. valerianoides is a perennial herb of the family Rubiaceae and has been used in herbal medicines for ages. Here, we used high-throughput sequencing technology Illumina MiSeq to study the structural and functional dynamics of the rhizosphere and endophytic fungi of K. valerianoides. RESULTS: The findings indicate that continuous planting has led to an increase in the richness and diversity of rhizosphere fungi, while concomitantly resulting in a decrease in the richness and diversity of root fungi. The diversity of endophytic fungal communities in roots was lower than that of the rhizosphere fungi. Ascomycota and Basidiomycota were the dominant phyla detected during the continuous cropping of K. valerianoides. In addition, we found that root rot directly affected the structure and diversity of fungal communities in the rhizosphere and the roots of K. valerianoides. Consequently, both the rhizosphere and endophyte fungal communities of root rot-infected plants showed higher richness than the healthy plants. The relative abundance of Fusarium in two and three years old root rot-infected plants was significantly higher than the control, indicating that continuous planting negatively affected the health of K. valerianoides plants. Decision Curve Analysis showed that soil pH, organic matter (OM), available K, total K, soil sucrase (S_SC), soil catalase (S_CAT), and soil cellulase (S_CL) were significantly related (p < 0.05) to the fungal community dynamics. CONCLUSIONS: The diversity of fungal species in the rhizosphere and root of K. valerianoides was reported for the first time. The fungal diversity of rhizosphere soil was higher than that of root endophytic fungi. The fungal diversity of root rot plants was higher than that of healthy plants. Soil pH, OM, available K, total K, S_CAT, S_SC, and S_CL were significantly related to the fungal diversity. The occurrence of root rot had an effect on the community structure and diversity of rhizosphere and root endophytic fungi.


Assuntos
Biodiversidade , Endófitos , Fungos , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Raízes de Plantas/microbiologia , DNA Fúngico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Doenças das Plantas/microbiologia , Ascomicetos/genética , Ascomicetos/classificação , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Filogenia , Micobioma
4.
Virol J ; 21(1): 140, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890675

RESUMO

BACKGROUND: The persistent infection of high-risk Human papillomavirus(HPV) is considered the main cause of cervical intraepithelial neoplasia and cervical cancer. But various cervical lesions caused by HPV infection can be properly prevented by timely vaccination. However, the distribution of HPV genotypes varies geographically. METHODS: Retrospective analysis of high-risk HPV prevalence of 16,150 women from 2020 to 2022 in xianning of China. HPV genotyping was performed using a PCR-RDB Kit that can detect 18 high-risk HPV genotypes recommended by China's National Medical Products Administration. The prevalence of 18 high-risk HPV genotypes and their relationship with cervical lesions as well as vaccine efficacy were analyzed. RESULTS: A total of 2431 women were confirmed to have different types of high-risk HPV infections. The overall positive rate reached 15.05%(2431/16,150). The most prevalent high-risk HPV genotypes were HPV52, 16, 58, 53, and 51. The prevalence of high-risk HPV reached peak at age ≤ 20(20.95%) and age ≥ 61(20.56%). The most prevalent high-risk HPV genotypes were HPV16, 58, 18, 33 and 52 in cervical cancer cases, HPV16, 52, 58, 33 and 18 in CIN2/3 cases, and HPV52, 58, 16, 53 and 18 in CIN1 cases, respectively. CONCLUSION: HPV16, 58 and 18 are the most dangerous and carcinogenic genotypes in xianning, China. Conducting epidemiological investigations on high-risk HPV has significant clinical value in guiding HPV vaccination work.


Assuntos
Genótipo , Papillomaviridae , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , China/epidemiologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Prevalência , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Estudos Retrospectivos , Papillomaviridae/genética , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/epidemiologia , Adolescente , Idoso , Displasia do Colo do Útero/virologia , Displasia do Colo do Útero/epidemiologia , Vacinas contra Papillomavirus/administração & dosagem , Papillomavirus Humano
5.
Langmuir ; 40(9): 4709-4718, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38388349

RESUMO

Constructing three-dimensional (3D) aligned nanofiber scaffolds is significant for the development of cardiac tissue engineering, which is promising in the field of drug discovery and disease mechanism study. However, the current nanofiber scaffold preparation strategy, which mainly includes manual assembly and hybrid 3D printing, faces the challenge of integrated fabrication of morphology-controllable nanofibers due to its cross-scale structural feature. In this research, a trench-guided electrospinning (ES) strategy was proposed to directly fabricate 3D aligned nanofiber scaffolds with alternative ES and a direct ink writing (DIW) process. The electric field effect of DIW poly(dimethylsiloxane) (PDMS) side walls on guiding whipping ES nanofibers was investigated to construct trench design rules. It was found that the width/height ratio of trenches greatly affected the nanofiber alignment, and the trench width/height ratio of 1.5 provided the nanofiber alignment degree over 60%. As a proof of principle, 3D nanofiber scaffolds with controllable porosity (60-80%) and alignment (30-60%) were fabricated. The effect of the scaffolds was verified by culturing human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), which resulted in the uniform 3D distribution of aligned hiPSC-CMs with ∼1000 µm thickness. Therefore, this printing strategy shows great potential for the efficient engineered tissue construction.


Assuntos
Nanofibras , Engenharia Tecidual , Humanos , Nanofibras/química , Alicerces Teciduais/química , Miócitos Cardíacos
6.
Analyst ; 149(3): 815-823, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38117163

RESUMO

The constrained enzymatic activity and aggregation challenges encountered by small-sized nanozymes pose obstacles to their practical utility, necessitating a strategy to mitigate aggregation and boost enzymatic catalytic efficiency. In this work, a negatively charged Eu MOF was utilized as the encapsulation matrix, encapsulating the small-sized nanozymes FeNCDs into the Eu MOF to synthesize an FeNCDs@Eu MOF. The dispersibility of the encapsulated FeNCDs was increased, and owing to the negative charge of the FeNCDs@Eu MOF, electrostatic pre-concentration of the positively charged target molecule tetracycline (TC) was facilitated, thereby amplifying the enzymatic catalytic efficiency of the FeNCDs. The response of the FeNCDs to TC increased by nearly 6 times upon encapsulation. The TC detection limit (LOD) of the FeNCDs@Eu MOF-based sensor is as low as 11.63 nM. The incorporation of fluorescence detection expanded the linear range of the sensor, rendering it more suitable for practical sample detection.


Assuntos
Colorimetria , Európio , Tetraciclina , Antibacterianos , Corantes Fluorescentes , Espectrometria de Fluorescência
7.
Environ Res ; 252(Pt 2): 118829, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582424

RESUMO

Municipal wastewater treatment processes consume a significant amount of energy and generate substantial carbon emissions. However, organic matters existing in municipal wastewater hold the potential as a valuable carbon source. Activated sludge has the potential to capture and recover the organic matters, thereby enriching carbon sources and facilitating subsequent sludge anaerobic digestion as well as in line with the concept of sustainable development. Based on above, this study investigated the enrichment and recovery characteristics and mechanisms of activated sludge adsorption on carbon sources in municipal wastewater, while optimizing the recovery conditions. The results indicated that insoluble organic matters, as well as a fraction of dissolved organic matters, can be effective recovered within approximately 40 min. Specifically, 74.1% of insoluble organic matters and 25.8% of soluble organic matters were successfully captured by the activated sludge, resulting in a 5.0% increase in sludge organic matter content. Moreover, activated sludge demonstrated remarkable recovery of particulate organic matters across various particle sizes, particularly larger particles (>5 µm) with high protein content. Notably, the dissolved biodegradable organics such as tryptophan and tyrosine protein-like substances according to 3D-EEM and lipids, proteins/amino sugars, and carbohydrates according to FT-ICR MS can be effectively recovered. Finally, the study revealed that the recovery of organic matters from the wastewater by activated sludge followed the pseudo-second-order kinetics model, with surface binding, hydrogen bonding and interparticle diffusion in sludge flocs as the primary adsorption mechanisms. This approach had abroad application prospects for improving the profitability of wastewater treatment plants.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Adsorção , Compostos Orgânicos/análise
8.
Environ Res ; 258: 119480, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909948

RESUMO

In this study, g-C3N4/PANI was prepared by in situ oxidative polymerization. Graphite-phase carbon nitride (g-C3N4) with surface defects was deposited onto the surface of conductive polyaniline (PANI) to form a p-n heterojunction. This construction aimed to create an efficient heterogeneous catalyst, increasing the surface defect level and active sites of the composite, and augmenting its capability to capture and transfer extracellular electrons under anaerobic conditions. This addresses the challenge of low efficiency in direct interspecies electron transfer between bacteria and archaea during anaerobic digestion for methane production. The results showed that the prepared g-C3N4/PANI increased the CH4 yield and CH4 production rate by 82% and 96%, respectively. Notably, the conductivity and XPS test results showed that the ratio of g-C3N4 to PANI was 0.15, and the composite exhibited favorable conductivity, with a uniform distribution of pyrrolic nitrogen, pyridinic nitrogen, and graphitic nitrogen, each accounting for approximately 30%. Furthermore, g-C3N4/PANI effectively enhanced the metabolic efficiency of intermediate products such as acetate and butyrate. Analysis of the microbial community structure revealed that g-C3N4/PANI led to a significant increase in the abundance of hydrogenotrophic methanogen Methanolinea (from 48% to 64%) and enriched Clostridium (a rise of 1%) with direct interspecies electron transfer capability. Microbial community function analysis demonstrated that the addition of g-C3N4/PANI boosted the activities of key enzymes involved in anaerobic digestion, including phosphate transacetylase (PTA), phospho-butyryl transferase (PTB), and NAD-independent lactate dehydrogenase (NNLD), by 47%, 135%, and 153%, respectively. This acceleration in enzymatic activity promoted the metabolism of acetyl-CoA, butyryl-CoA, and pyruvate. Additionally, the function of ABC transporters was enhanced, thereby improving the efficiency of material and energy exchange among microorganisms.

9.
Environ Res ; 241: 117660, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37979928

RESUMO

Cow dung generates globally due to increased beef and milk consumption, but its treatment efficiency remains low. Previous studies have shown that riboflavin-loaded conductive materials can improve anaerobic digestion through enhance direct interspecies electron transfer (DIET). However, its effect on the practical anaerobic digestion of cow dung remained unclear. In this study, carbon cloth loaded with riboflavin (carbon cloth-riboflavin) was added into an anaerobic digester treating cow dung. The carbon cloth-riboflavin reactor showed a better performance than other two reactors. The metagenomic analysis revealed that Methanothrix on the surface of the carbon cloth predominantly utilized the CO2 reduction for methane production, further enhanced after riboflavin addition, while Methanothrix in bulk sludge were using the acetate decarboxylation pathway. Furthermore, the carbon cloth-riboflavin enriched various major methanogenic pathways and activated a large number of enzymes associated with DIET. Riboflavin's presence altered the microbial communities and the abundance of functional genes relate to DIET, ultimately leading to a better performance of anaerobic digestion for cow dung.


Assuntos
Carbono , Elétrons , Bovinos , Animais , Anaerobiose , Metano , Reatores Biológicos , Esgotos
10.
Surg Endosc ; 38(5): 2788-2794, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38587640

RESUMO

AIM: To analyze efficacy of endoscopic lithotripsy combined with drug lithotripsy as compared with drug lithotripsy for the treatment of phytobezoars. METHODS: We collected and evaluated case records of 165 patients with phytobezoars from 2014 to 2023. And we analyzed demographic and clinical characteristics, imaging features, endoscopic features, complications of phytobezoars, and compared efficacy between endoscopic lithotripsy combined with drug lithotripsy (Group A) and drug lithotripsy (sodium bicarbonate combined with proton pump inhibitor) (Group B). RESULTS: The median age of patients with phytobezoars was 67.84 ± 4.286 years old. Abdominal pain was the most common symptom and peptic ulcers (67.5%) were the most common complication. Bezoar-induced ulcers were more frequent in the gastric angle. The success rate of phytobezoars vanishing in Group A and Group B were similar (92.3% vs. 85.1% within 48 h, 98.7% vs. 97.7% within a week), while the average hospitalization period, average hospitalization cost, second endoscopy rate, and average endoscopic operation time were significantly lower in patients in Group B than in Group A. CONCLUSION: Drug lithotripsy is the preferred effective and safe treatment option for phytobezoars. We advise that an endoscopy should be completed after 48 h for drug lithotripsy.


Assuntos
Bezoares , Litotripsia , Humanos , Bezoares/terapia , Masculino , Feminino , Litotripsia/métodos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Inibidores da Bomba de Prótons/administração & dosagem , Resultado do Tratamento , Bicarbonato de Sódio/administração & dosagem , Bicarbonato de Sódio/uso terapêutico , Terapia Combinada , Dor Abdominal/etiologia , Dor Abdominal/terapia
11.
Growth Factors ; 41(4): 210-220, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37735894

RESUMO

OBJECTIVE: To observe the mechanism of IGFBP2 knock-down in improving lung fibrosis and inflammation through STAT3 pathway in rats with severe pneumonia. MATERIALS AND METHODS: First, SP rat model was established. Then rats were divided into the Control group, the SP group, the SP + Lv-vector shRNA group, the SP + Lv-IGFBP2 shRNA group, the SP + Lv-vector group, and the SP + Lv-IGFBP2 group. The mRNA and protein levels of IGFBP2, NOS, CD206 and Arg 1 were detected by RT-qPCR and Western blot. IHC was used to check the positive expression of IGFBP2 and MCP1. A fully automated blood gas analyzer was used to detected PaCO2, CO2 content, PaO2 and SaO2. HE and Masson staining were performed to observe the lung tissue injury and collagen deposition of rats in each group. ELISA assays were used to calculate the levels of inflammatory factors IL-1ß, IL-6, TNF-α, IL-4, and IL-10. Flow cytometry was conducted to acquire the ratio of M1-type AMs and M2-type AMs. RESULTS: Compared with the Control group, IGFBP2, iNOS, CD206, and Arg1 mRNA and protein expression levels, IGFBP2 and MCP1 positive expressions, PaCO2, p-STAT3/STAT3, p-JAK2/JAK2, IL-1ß, IL-6, and TNF-α levels, the number of AMs and neutrophils, the proportion of M1 type AMs and the expressions of α-SMA, Collagen-I, Collagen III, and Fibronectin were significantly increased in SP rats (p < 0.05), while PaCO2, CO2, and SaO2, IL-4 and IL-10 levels, and the proportion of M2 type AMs decreased (p < 0.05). However, the knockdown of IGFBP2 reversed the above index trends. CONCLUSION: Knock-down of IGFBP2 ameliorated lung injury in SP rats, inhibited inflammation and pulmonary fibrosis, and promoted M2-type transformation of AMs by activating the STAT3 pathway.

12.
Anal Chem ; 95(4): 2390-2397, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36638045

RESUMO

The detection of trypsin is significantly important for both clinical diagnosis and disease treatment. In this study, an innovative multicolor sensor for trypsin detection has been established based on the regulation of the peroxidase activity of bovine serum albumin-coated gold nanoclusters (BSA-Au NCs) and efficient etching of gold nanobipyramids (Au NBPs). BSA-Au NCs have slight peroxidase enzyme activity and can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to generate TMB+, while trypsin can hydrolyze BSA ligands on the surface of BSA-Au NCs, thus exposing more catalytic active sites of BSA-Au NCs and resulting in the enhancement of the peroxidase activity of BSA-Au NCs, hence more TMB+ is generated. Under acidic conditions, TMB+ can etch Au NBPs efficiently, consequently affecting the aspect ratio of Au NBPs accompanied by the ultraviolet-visible (UV-vis) spectra blue shifting of the system. Furthermore, this also results in color variations that can be distinguished and recognized by naked eyes without any expensive and sophisticated instruments. This multicolor sensor has an available linear relationship with the logarithm of the trypsin concentration in the range of 0.1-100 µg/mL, and the detection limit is 0.045 µg/mL. The designed sensor has been used to detect the concentration of trypsin in human serum samples from healthy individuals and pancreatitis patients with satisfactory results.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Tripsina/química , Soroalbumina Bovina/química , Ouro/química , Peroxidases , Nanopartículas Metálicas/química
13.
Anal Chem ; 95(37): 14127-14134, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37676272

RESUMO

In this work, combined with the high amplification efficiency of hybridization chain reaction (HCR), high specificity of the CRISPR/Cas12a system, and convenience of the homogeneous electrochemiluminescence (ECL) assay based on the regulation of negative charge on the reporting probes, a sensitive ECL biosensor for hepatitis B virus DNA (chosen as a model target) had been developed. The initiator chain trigger DNA that can induce HCR amplification is modified on the surface of ruthenium bipyridine-doped silica nanoparticles (Ru@SiO2 NPs) first, and large amounts of negative charges modified on the particles were achieved through the HCR amplification reaction. The efficiency of the nanoparticles reaching the negatively charged working electrode can be regulated and realize the change of the ECL signal. In addition, long DNA on the surface of the luminescent body may prevent the coreactant from entering the pore to react with ruthenium bipyridine. These factors combine to produce a low-background system. The presence of the target can activate the CRISPR/Cas12a system and make trigger DNA disappear from the nanoparticle surface, and strong ECL can be detected. The sensor does not require a complex electrode modification; therefore, it has better reproducibility. Additionally, due to dual signal amplification, the sensor has a high sensitivity. In the range of 10 fM to 10 nM, the ECL intensity exhibits a strong linear relationship with the logarithm of the target concentration, and the detection limit is 7.41 fM. This sensor has shown high accuracy in detecting clinical samples, which holds significant potential for application in clinical testing.


Assuntos
Nanopartículas , Rutênio , Vírus da Hepatite B/genética , Sistemas CRISPR-Cas , Reprodutibilidade dos Testes , Dióxido de Silício , DNA
14.
Anal Chem ; 95(50): 18603-18610, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38048177

RESUMO

Terminal deoxynucleotidyl transferase (TdT) is upregulated in several types of leukemia and is considered a disease biomarker and a potential therapeutic target for leukemia. In this research, a homogeneous electrochemiluminescence (ECL) method based on the control of surface charge and morphology of tris (2,2'-bipyridine) ruthenium(II) chloride hexahydrate-doped silica nanoparticles (Ru@SiO2 NPs) has been designed for TdT activity detection. A small amount of short single-stranded DNA (ssDNA) was modified onto the surface of Ru@SiO2 NPs, and the nanoparticles with a slight positive charge experienced electrostatic attraction with the indium tin oxide (ITO) electrode with a negative charge, so relatively high ECL signals had been detected. Under the action of TdT, the ssDNA was significantly elongated, carrying numerous negative charges on its phosphate backbone, so the overall negative charge of the reporter nanoparticles was enhanced, resulting in a strong electrostatic repulsion with the ITO electrode. Simultaneously, the long ssDNA wrapped around the nanoparticles hindered the approach of the coreactant. Due to the dual effects, the ECL response of the system decreased. The constructed biosensor exhibited excellent sensitivity toward TdT over a range spanning from 1 to 100 U/L. The limit of detection is as low as 1.78 U/L. The developed approach was effectively applied to detect TdT activity in leukemic patients' leukocyte extracts.


Assuntos
Técnicas Biossensoriais , Leucemia , Nanopartículas , Humanos , DNA Nucleotidilexotransferase , Dióxido de Silício , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , DNA de Cadeia Simples , Técnicas Biossensoriais/métodos
15.
Anal Chem ; 95(48): 17670-17678, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37992131

RESUMO

For rapid and sensitive detection of miRNA-210, which is important for improving the reliability of clinical diagnosis of breast cancer, a dual-signal mode ratiometric photoelectrochemical (PEC) sensor based on a Au/GaN photoanode is proposed. First, a DNA probe was designed that could complement the target miRNA-210. Then, another G-rich DNA sequence was designed to mismatch the probe and form a double-stranded DNA (dsDNA). Upon addition of the target, the dsDNA unwinds from its binding site and releases G-rich single-stranded DNA. In the presence of Mg2+ and K+, this single-stranded DNA molecule spontaneously forms a G-quadruplex structure, facilitating the rapid transport of photogenerated holes, thereby increasing the photocurrent response of Au/GaN and enabling sensitive label-free detection of miRNA-210. By control of different pH values, a response signal was generated at pH 8, while a reference signal was produced at pH 5. The designed PEC system shows a high potential for the development of miRNA-210 detection. Ultimately, the response signal-to-reference signal ratio was used as the variable, and a broad linear span ranging from 10 fM to 1 nM (R2 = 0.993) has been exhibited, with a detection threshold of 3 fM (S/N = 3). The designed PEC platform shows potential for the development of other disease markers.


Assuntos
Técnicas Biossensoriais , MicroRNAs , DNA de Cadeia Simples , Reprodutibilidade dos Testes , Ouro/química , DNA/química , Limite de Detecção , Técnicas Eletroquímicas
16.
J Org Chem ; 88(13): 8791-8801, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37260330

RESUMO

A [6 + 1] annulation reaction via cascade 1,6-hydride transfer/cyclization is reported to construct a polycyclic 3,4-fused azepinoindole skeleton. The newly designed 4-amino-indole-3-carbaldehyde is applied as a novel six-atom synthon, interacting with arylamines and malononitrile to achieve the [6 + 1] annulation. Notably, the reaction proceeds smoothly under redox-neutral and metal-free conditions, providing a wide range of azepinoindoles in up to 94% yields, with water as the only byproduct. Besides, the advantage of high step- and atom-economy further highlights the practicality of this methodology.


Assuntos
Paládio , Catálise , Ciclização , Oxirredução
17.
Analyst ; 148(13): 2983-2991, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37306227

RESUMO

A novel photoelectrochemical (PEC) sensor was constructed for the highly sensitive detection of reduced glutathione (GSH) based on the multiple catalytic properties of phosphotungstic acid (PTA). In this work, the catalytic properties of PTA were applied to PEC sensing for the first time and interpreted in detail. First, PTA as an electron acceptor can inhibit the complexation of photogenerated electron-hole pairs in p-Cu2O, thus significantly increasing the photogenerated current of p-type semiconductor material Cu2O. Secondly, when GSH is oxidized to oxidized glutathione (GSSG) by photogenerated holes on the photocathode, PTA is able to reduce GSSG to GSH by transferring protons, forming a redox cycle regeneration process of GSH. Finally, the relatively large amount of PTA in the background solution was able to pre-oxidize interfering substances such as L-cysteine and ascorbic acid, which improved the selectivity of the method. Under the optimal experimental conditions, the linear range of the PEC sensor response to GSH was 0.050-100 nmol L-1, with a detection limit as low as 0.017 nmol L-1 (S/N = 3), which can be applied to the detection of GSH content in cell lysate samples.


Assuntos
Técnicas Biossensoriais , Glutationa , Dissulfeto de Glutationa , Ácido Fosfotúngstico , Semicondutores , Oxirredução , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção
18.
Analyst ; 148(20): 4995-5001, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37728304

RESUMO

Two-dimensional (2D) layered MoS2 has good dispersion and adsorption properties, but being a narrow bandgap semiconductor limits its application in photoelectric sensing. In this study, a homogeneous photoelectrochemical sensor based on three-dimensional (3D) ZnO/Au/2D MoS2 is proposed for the ultrasensitive detection of tetracycline (TET). MoS2 is uniformly embedded on the 3D ZnO/Au surface by ordered self-assembly. The physical method of π-π interaction of MoS2 replaces the conventional use of chemically modifying aptamers on the electrode material surface. Under optimal conditions, this method has been successfully applied to the detection of TET in milk, honey, pig kidney and pork samples with reliable results. We believe that this study presents a method for the preparation of sensing carriers and target detection with great potential for application.

19.
Sens Actuators B Chem ; 379: 133223, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36573100

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is rampant all over the world, and rapid and effective virus detection is the best auxiliary to curb the spread of the epidemic. A diagnosis can only be made if two or more different nucleic acid sequences are confirmed at the same time, and in most of traditional detection technologies, these target sequences have been detected separately. In this work, an electrochemiluminescent (ECL) biosensor employing a single ECL probe as signal output and responding to dual-target simultaneously is proposed for the first time. Taking the two sequences located in ORF 1ab region and N region of SARS-CoV-2 gene sequence as the model target and nitrogen doped carbon quantum dots (CDs) as ECL beacon, supplemented with catalytic hairpin assembly (CHA) reaction for signal amplification, the presented strategy has been successfully applied to the rapid detection of SARS-CoV-2. The developed SARS-CoV-2 biosensor based on the series CHA systems can realize the quantitative determination of SARS-CoV-2 in the range of 50 fM to 200 pM within 40 min. Moreover, the clinical validity of this method has been verified by the high consistency between the detection results of using this method and those using RT-qPCR for seven clinical pharyngeal swab samples.

20.
Cell Mol Life Sci ; 79(3): 175, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35244772

RESUMO

FK506-binding protein 51 (encoded by Fkpb51, also known as Fkbp5) has been associated with stress-related mental illness. To investigate its function, we studied the morphological consequences of Fkbp51 deletion. Artificial Intelligence-assisted morphological analysis revealed that male Fkbp51 knock-out (KO) mice possess more elongated dentate gyrus (DG) but shorter hippocampal height in coronal sections when compared to WT. Primary cultured Fkbp51 KO hippocampal neurons were shown to exhibit larger dendritic outgrowth than wild-type (WT) controls and pharmacological manipulation experiments suggest that this may occur through the regulation of microtubule-associated protein. Both in vitro primary culture and in vivo labeling support a role for FKBP51 in the regulation of microtubule-associated protein expression. Furthermore, Fkbp51 KO hippocampi exhibited decreases in ßIII-tubulin, MAP2, and Tau protein levels, but a greater than 2.5-fold increase in Parkin protein. Overexpression and knock-down FKBP51 demonstrated that FKBP51 negatively regulates Parkin in a dose-dependent and ubiquitin-mediated manner. These results indicate a potential novel post-translational regulatory mechanism of Parkin by FKBP51 and the significance of their interaction on disease onset. KO has more flattened hippocampus using AI-assisted measurement Both pyramidal cell layer (PCL) of CA and granular cell layer (GCL) of DG distinguishable as two layers: deep cell layer and superficial layer. Distinct MAP2 expression between deep and superficial layer between KO and WT, Higher Parkin expression in KO brain Mechanism of FKBP51 inhibition resulting in Parkin, MAP2, Tau, and Tubulin expression differences between KO and WT mice, and resulting neurite outgrowth differences.


Assuntos
Hipocampo/metabolismo , Proteínas de Ligação a Tacrolimo/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Encéfalo/anatomia & histologia , Células Cultivadas , Hipocampo/anatomia & histologia , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a Tacrolimo/antagonistas & inibidores , Proteínas de Ligação a Tacrolimo/deficiência , Proteínas de Ligação a Tacrolimo/metabolismo , Tubulina (Proteína)/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Regulação para Cima , Proteínas tau/metabolismo
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