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1.
Anal Bioanal Chem ; 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39354157

RESUMEN

Tuberculosis is a highly infectious disease caused by the bacterium Mycobacterium tuberculosis, and the spread of this agent has caused serious health problems worldwide. The rapid and accurate detection of M. tuberculosis is essential for controlling the spread of infection and for preventing the emergence of multidrug-resistant strains. In this study, the powerful trans-cleavage ability of CRISPR-Cas12a for ssDNA was combined with a surface-enhanced Raman spectroscopy (SERS)-based strategy to establish a CRISPR-SERS sensor for the hypersensitive detection of M. tuberculosis DNA. We observed a linear relationship between the concentration of M. tuberculosis DNA and the output signal over the range of 5 to 100 pM. The equation describing the standard curve was y = 24.10x + 1594, with R2 = 0.9914. The limit of detection was as low as 4.42 pM for genomic DNA, and a plasmid containing an M. tuberculosis-specific sequence was detected at 5 copy/µL. A detection accuracy of 100% was achieved in the analysis of DNA isolated from the sputum of hospitalized patients with tuberculosis. The entire detection process is simple to deploy and only takes 50 min and results in the sensitive and specific detection of M. tuberculosis DNA. This study provides a new method for the detection of tuberculosis. The tool is stable and can be utilized on-site, and it thus broadens the diagnostic application of CRISPR-Cas12a-based sensor technology.

2.
Small Methods ; : e2401139, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235422

RESUMEN

The development of bifunctional, non-noble metal-based electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) through morphology and electronic engineering is highly attractive for efficient water splitting. Herein, hierarchical nanoarrays consisting of crystalline cobalt phosphide nanorods covered by amorphous Fe-doped cobalt phosphide nanocuboids (CoP/FeCoPx) are constructed as bifunctional catalysts for both HER and OER. Experimental results and theoretical calculations reveal that the catalysts exhibit balanced dual-catalytic properties due to simultaneous introduction of Fe doping and phosphorus vacancies, leading to an optimized electronic structure of the CoP/FeCoPx. Furthermore, the hierarchical nanoarrays made of crystalline/amorphous heterostructures significantly enhance the performance of the electrocatalysts. As a result, the CoP/FeCoPx catalyst demonstrates remarkable performance in both HER and OER, with overpotentials of 74 and 237 mV at 10 mA cm-2 in 1 m KOH, respectively, as well as a low cell voltage of 1.53 V at 10 mA cm-2 for alkaline overall water splitting. This work integrates the morphology engineering involving design of hierarchical crystalline/amorphous nanoarrays and the electronic engineering through Fe doping and phosphorus vacancies for efficient water electrolysis. It may open a new route toward rational design and feasible fabrication of high-performance, multifunctional, non-noble metal-based electrocatalysts for energy conversion.

3.
J Phys Chem A ; 128(34): 7105-7113, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39151122

RESUMEN

Self-reaction of propargyl (C3H3) radical is the main pathway to benzene, the formation of which is the rate-controlling step toward the formation of polycyclic aromatic hydrocarbons (PAHs) and soot. Oxidation of C3H3 is a promising strategy to inhibit the formation of hazardous PAHs and soot. In the present study, we studied the C3H3 + O2 reaction from 650 to 1100 K in a laminar flow reactor and identified the intermediates and products by synchrotron VUV photoionization mass spectrometry. 2-Propynal, ethenone, formaldehyde, CO, CO2, C2H2, C2H4, and C3O2 were identified. Among them, 2-propynal, ethenone, and formaldehyde provided direct evidence for the branching reaction of C3H3 + O2 → HCCCHO + OH, C3H3 + O2 → H2CCO + CHO, and C3H3 + O2 → H2CO + CHCO, respectively. Potential energy surface calculation and mechanistic analysis of the C3O2 formations implied that C3H3 + O2 → CCCHO + H2O and C3H3 + O2 → HCCCO + H2O could occur, despite lacking direct observations of CCCHO and HCCCO radicals. The formation of ethenone and CO suggested the occurrence of the two CO elimination channels. We incorporated these validated reactions and the corresponding rate coefficients in the kinetic model of NUIGMech1.3, and the simulation showed obvious improvements toward the measured mole fractions of C3H3 and H2CCO, suggesting that the new C3H3 + O2 reaction channels were crucial in the overall combustion modeling of the important intermediate propyne (C3H4).

4.
Open Life Sci ; 19(1): 20220927, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39091626

RESUMEN

New drugs for the treatment of bacterial vaginosis (BV) are yet to be developed due to concerns that they may contribute to the increase in antibiotic resistance in BV. Antimicrobial peptides (AMPs) are one of the most promising options for next-generation antibiotics. In this study, we investigated the bacteriostatic activity of the AMPs Pexiganan, plectasin, melittin, and cathelicidin-DM against Gram-negative and Gram-positive bacteria both in vitro and in a mouse model of BV infection. The results showed that Pexiganan, melittin, and cathelicidin-DM had significant antibacterial activity against both Gram-negative and Gram-positive bacteria. AMPs have great potential for clinical application in the treatment of vaginitis, and this study provides an experimental basis for their use in the active immunoprophylaxis of BV.

5.
Biol Trace Elem Res ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958867

RESUMEN

Cadmium(Cd) is a toxic heavy metal widely present in the environment, capable of accumulating in the liver and causing liver damage. In this study, the mechanism of cadmium-induced liver fibrosis in chickens was investigated from the perspective of hepatocyte epithelial-mesenchymal transition (EMT) based on the establishment of a model of chicken cadmium toxicity and a model of cadmium-stained cells in a chicken hepatocellular carcinoma cell line (LMH). The 7-day-old chickens were randomly divided into the regular group (C group) and cadmium poisoning group (Cd group), and the entire test cycle was 60 days. Three sampling time points of 20 days, 40 days, and 60 days were established. By testing the liver coefficient, histopathological and ultrastructural changes in chicken livers were observed. The enzyme activities of liver function and the expression changes of fibrosis markers (COL1A1, Fibronectin), epithelial-mesenchymal transition markers (E-cadherin, Vimentin, and α-SMA), and the critical factors of the TGF-ß/SMAD signaling pathway (TGF-ß1, SMAD 2, and SMAD 3) were detected in the liver expression changes. The results showed that at the same sampling time point, the chicken liver coefficient in group Cd was significantly higher than that in control group (P < 0.01); the activities of the liver function enzymes ALT and AST in chickens in the Cd group were significantly higher than those in the C group (P < 0.01); liver hepatocytes degenerated and necrotic, the number of erythrocytes in the blood vessels was increased, and inflammatory cells infiltrated in the sinusoidal gap; the perisinusoidal gap of the liver was enlarged, and there was an apparent aggregation of collagen fibers in the intervening period as seen by transmission electron microscopy. The results of Masson staining showed that the percentage of fiber area was significantly higher in the chickens' livers of the Cd group. The fiber area percentage was significantly higher. The results of real-time fluorescence quantitative PCR and Western Blot showed that the expression of E-cadherin in the livers of chickens in the Cd group was significantly lower than that in the C group (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-ß1, SMAD 2, and SMAD 3 was significantly higher than that in the C group (P < 0.01). The results of in vitro assays showed that in the LMH cell model established by adding trimethylamine N-oxide, an activator of the TGF-ß/SMAD signaling pathway, and oxidized picric acid, an inhibitor of the TGF-ß/SMAD signaling pathway, the expression of E-cadherin was significantly reduced in cadmium-stained LMH cells (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-ß, SMAD 2, and SMAD 3 was significantly elevated (P < 0.01). Cadmium and Trimethylamine N-oxide, an activator of the TGF-ß/SMAD signaling pathway, promoted the expression of these factors. In contrast, the inhibitor of the TGF-ß/SMAD signaling pathway, Oxymatrine, a TGF-ß/SMAD signaling pathway inhibitor, significantly slowed down these changes. These results suggest that cadmium induces hepatic epithelial-mesenchymal transition by activating the TGF-ß/SMAD signaling pathway in chicken hepatocytes, promoting hepatic fibrosis.

6.
Rev Med Virol ; 34(4): e2570, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38964866

RESUMEN

The question of whether patients in the immune-tolerant (IT) phase of chronic hepatitis B virus (HBV) infection should undergo antiviral therapy and determine the optimal regimen remains unclear. A comprehensive search of PubMed, Embase, MEDLINE, Cochrane Library, and Wanfang Data from inception to 5 December 2023, was conducted. Studies reporting on key outcomes such as HBV DNA undetectability, HBeAg loss or seroconversion, HBsAg loss or seroconversion, and hepatocellular carcinoma (HCC) incidence in patients in the IT phase of chronic HBV infection were included. In total, 23 studies were incorporated. Approximately 4% of patients in the IT phase achieved spontaneous HBeAg loss over 48 weeks of follow-up. Antiviral therapy demonstrated a favourable impact on HBV DNA negative conversion (Children: risk ratios [RR] = 6.83, 95% CI: 2.90-16.05; Adults: RR = 25.84, 95% CI: 6.47-103.31) and HBsAg loss rates (Children: RR = 9.49, 95% CI: 1.74-51.76; Adults: RR = 7.35, 95% CI: 1.41-38.27) for patients in the IT phase. Subgroup analysis revealed that in adult patients in the IT phase, interferon plus nucleos(t)ide analogues (NA)-treated patients exhibited a higher pooled rate of HBsAg loss or seroconversion than those treated with NA monotherapy (9% vs. 0%). Additionally, the pooled annual HCC incidence for patients in the IT phase was 3.03 cases per 1000 person-years (95% CI: 0.99-5.88). Adult patients in the IT phase had a significantly lower HCC incidence risk than HBeAg-positive indeterminate phase patients (RR = 0.46, 95% CI: 0.32-0.66), with no significant differences observed between IT and immune-active phases. Presently, there is insufficient evidence solely based on reducing the risk of HCC incidence, to recommend treating patients in the IT phase of chronic HBV infection. However, both adult and paediatric patients in the IT phase responded well to antiviral therapy, showing favourable rates of HBsAg loss or seroconversion.


Asunto(s)
Antivirales , Carcinoma Hepatocelular , Antígenos e de la Hepatitis B , Hepatitis B Crónica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/virología , Carcinoma Hepatocelular/inmunología , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/inmunología , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/virología , Neoplasias Hepáticas/inmunología , Antivirales/uso terapéutico , Antígenos e de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Incidencia , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , ADN Viral/sangre , Tolerancia Inmunológica , Resultado del Tratamiento , Seroconversión
7.
J Nanobiotechnology ; 22(1): 341, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890636

RESUMEN

Tumor-associated macrophages (TAMs) are pivotal within the immunosuppressive tumor microenvironment (TME), and recently, have attracted intensive attention for cancer treatment. However, concurrently to promote TAMs repolarization and phagocytosis of cancer cells remains challenging. Here, a TAMs-targeted albumin nanoparticles-based delivery system (M@SINPs) was constructed for the co-delivery of photosensitizer IR820 and SHP2 inhibitor SHP099 to potentiate macrophage-mediated cancer immunotherapy. M@SINPs under laser irradiation can generate the intracellular reactive oxygen species (ROS) and facilitate M2-TAMs to an M1 phenotype. Meanwhile, inhibition of SHP2 could block the CD47-SIRPa pathway to restore M1 macrophage phagocytic activity. M@SINPs-mediated TAMs remodeling resulted in the immunostimulatory TME by repolarizing TAMs to an M1 phenotype, restoring its phagocytic function and facilitating intratumoral CTLs infiltration, which significantly inhibited tumor growth. Furthermore, M@SINPs in combination with anti-PD-1 antibody could also improve the treatment outcomes of PD-1 blockade and exert the synergistic anticancer effects. Thus, the macrophage repolarization/phagocytosis restoration combination through M@SINPs holds promise as a strategy to concurrently remodel TAMs in TME for improving the antitumor efficiency of immune checkpoint block and conventional therapy.


Asunto(s)
Antígeno CD47 , Inmunoterapia , Nanopartículas , Fagocitosis , Microambiente Tumoral , Macrófagos Asociados a Tumores , Animales , Inmunoterapia/métodos , Ratones , Nanopartículas/química , Macrófagos Asociados a Tumores/inmunología , Microambiente Tumoral/efectos de los fármacos , Línea Celular Tumoral , Neoplasias/terapia , Neoplasias/inmunología , Humanos , Especies Reactivas de Oxígeno/metabolismo , Ratones Endogámicos C57BL , Receptores Inmunológicos/metabolismo , Femenino
8.
J Integr Plant Biol ; 66(7): 1500-1516, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38751028

RESUMEN

Tapetum, the innermost layer of the anther wall, provides essential nutrients and materials for pollen development. Timely degradation of anther tapetal cells is a prerequisite for normal pollen development in flowering plants. Tapetal cells facilitate male gametogenesis by providing cellular contents after highly coordinated programmed cell death (PCD). Tapetal development is regulated by a transcriptional network. However, the signaling pathway(s) involved in this process are poorly understood. In this study, we report that a mitogen-activated protein kinase (MAPK) cascade composed of OsYDA1/OsYDA2-OsMKK4-OsMPK6 plays an important role in tapetal development and male gametophyte fertility. Loss of function of this MAPK cascade leads to anther indehiscence, enlarged tapetum, and aborted pollen grains. Tapetal cells in osmkk4 and osmpk6 mutants exhibit an increased presence of lipid body-like structures within the cytoplasm, which is accompanied by a delayed occurrence of PCD. Expression of a constitutively active version of OsMPK6 (CA-OsMPK6) can rescue the pollen defects in osmkk4 mutants, confirming that OsMPK6 functions downstream of OsMKK4 in this pathway. Genetic crosses also demonstrated that the MAPK cascade sporophyticly regulates pollen development. Our study reveals a novel function of rice MAPK cascade in plant male reproductive biology.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas Quinasas Activadas por Mitógenos , Oryza , Proteínas de Plantas , Polen , Polen/genética , Polen/crecimiento & desarrollo , Oryza/genética , Oryza/enzimología , Oryza/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , Sistema de Señalización de MAP Quinasas , Fertilidad/fisiología , Fertilidad/genética , Mutación/genética , Flores/genética , Flores/fisiología
9.
Nat Commun ; 15(1): 4196, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760357

RESUMEN

Precious metals are core assets for the development of modern technologies in various fields. Their scarcity poses the question of their cost, life cycle and reuse. Recently, an emerging catalysis employing contact-electrification (CE) at water-solid interfaces to drive redox reaction, called contact-electro-catalysis (CEC), has been used to develop metal free mechano-catalytic methods to efficiently degrade refractory organic compounds, produce hydrogen peroxide, or leach metals from spent Li-Ion batteries. Here, we show ultrasonic CEC can successfully drive the reduction of Ag(ac), Rh3+, [PtCl4]2-, Ag+, Hg2+, Pd2+, [AuCl4]-, and Ir3+, in both anaerobic and aerobic conditions. The effect of oxygen on the reaction is studied by electron paramagnetic resonance (EPR) spectroscopy and ab-initio simulation. Combining measurements of charge transfers during water-solid CE, EPR spectroscopy and gold extraction experiments help show the link between CE and CEC. What's more, this method based on water-solid CE is capable of extracting gold from synthetic solutions with concentrations ranging from as low as 0.196 ppm up to 196 ppm, reaching in 3 h extraction capacities ranging from 0.756 to 722.5 mg g-1 in 3 h. Finally, we showed CEC is employed to design a metal-free, selective, and recyclable catalytic gold extraction methods from e-waste aqueous leachates.

10.
J Am Chem Soc ; 146(19): 13571-13579, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38710105

RESUMEN

Based on quantum mechanically guided experiments that observed elusive intermediates in the domain of inception that lies between large molecules and soot particles, we provide a new mechanism for the formation of carbonaceous particles from gas-phase molecular precursors. We investigated the clustering behavior of resonantly stabilized radicals (RSRs) and their interactions with unsaturated hydrocarbons through a combination of gas-phase reaction experiments and theoretical calculations. Our research directly observed a sequence of covalently bound clusters (CBCs) as key intermediates in the evolution from small RSRs, such as benzyl (C7H7), indenyl (C9H7), 1-methylnaphthyl (1-C11H9), and 2-methylnaphthyl (2-C11H9), to large polycyclic aromatic hydrocarbons (PAHs) consisting of 28 to 55 carbons. We found that hydrogen abstraction and RSR addition drive the formation and growth of CBCs, leading to progressive H-losses, the generation of large PAHs and PAH radicals, and the formation of white smoke (incipient carbonaceous particles). This mechanism of progressive H-losses from CBCs (PHLCBC) elucidates the crucial relationship among RSRs, CBCs, and PAHs, and this study provides an unprecedentedly seamless path of observed assembly from small RSRs to large nanoparticles. Understanding the PHLCBC mechanism over a wide temperature range may enhance the accuracy of multiscale models of soot formation, guide the synthesis of carbonaceous nanomaterials, and deepen our understanding of the origin and evolution of carbon within our galaxy.

11.
Nanomaterials (Basel) ; 14(10)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38786793

RESUMEN

In order to prepare biomass-derived carbon materials with high specific capacitance at a low activation temperature (≤700 °C), nanoporous carbon materials were prepared from zanthoxylum bungeanum peels and seeds via the pyrolysis and KOH-activation processes. The results show that the optimal activation temperatures are 700 °C and 600 °C for peels and seeds. Benefiting from the hierarchical pore structure (micropores, mesopores, and macropores), the abundant heteroatoms (N, S, and O) containing functional groups, and plentiful electrochemical active sites, the PAC-700 and SAC-600 derive the large capacities of ~211.0 and ~219.7 F g-1 at 1.0 A g-1 in 6 M KOH within the three-electrode configuration. Furthermore, the symmetrical supercapacitors display a high energy density of 22.9 and 22.4 Wh kg-1 at 7500 W kg-1 assembled with PAC-700 and SAC-600, along with exceptional capacitance retention of 99.1% and 93.4% over 10,000 cycles at 1.0 A g-1. More significantly, the contribution here will stimulate the extensive development of low-temperature activation processes and nanoporous carbon materials for electrochemical energy storage and beyond.

12.
J Fluoresc ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607530

RESUMEN

Hypochloric acid (HClO) is a reactive oxygen species (ROS) that functions as a bacteriostatic and disinfectant in food production. Excessive levels of ClO-, however, have been linked to various health issues, including cardiovascular diseases (Halliwell and Gutteridge in Oxford University press, USA, 2015), arthritis, and neurodegenerative diseases (Heinzelmann and Bauer in Biol Chem. 391(6):675-693, 2010). Therefore, synthesizing highly selective and sensitive probes for rapidly detecting endogenous ClO- in daily foods is currently a popular research topic (Kalyanaraman et al. in Redox Biol. 15:347-362, 2018; Winterbourn in Nat Chem Biol. 4(5):278-286, 2008; Turrens in J Physiol. 552(2):335-344, 2003). Thus, we have developed two highly selective ratiometric fluorescent probes (Probe1 and Probe2) based on indole-phenothiazine to detect ClO- in common vegetables, fruits and beverages qualitatively and quantitatively. Moreover, Both Probe1 and Probe2 have shown good specificity and stability, with high fluorescence intensity and long duration (Feng et al. in Adv Sci. 5:1800397, 2018; Wei et al. in Angew Chem. 131(14):4595-4599, 2019; Baruah et al. in J Mater Chem B, 2022).

13.
Molecules ; 29(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38611812

RESUMEN

Antibiotic resistance has emerged as a grave threat to global public health, leading to an increasing number of treatment failures. Antimicrobial peptides (AMPs) are widely regarded as potential substitutes for traditional antibiotics since they are less likely to induce resistance when used. A novel AMP named Brevinin-1BW (FLPLLAGLAASFLPTIFCKISRKC) was obtained by the Research Center of Molecular Medicine of Yunnan Province from the skin of the Pelophylax nigromaculatus. Brevinia-1BW had effective inhibitory effects on Gram-positive bacteria, with a minimum inhibitory concentration (MIC) of 3.125 µg/mL against Enterococcus faecalis (ATCC 29212) and 6.25 µg/mL against both Staphylococcus aureus (ATCC 25923) and multidrug-resistant Staphylococcus aureus (ATCC 29213) but had weaker inhibitory effects on Gram-negative bacteria, with a MIC of ≥100 µg/mL. Studies using scanning electron microscopy (SEM) and flow cytometry have revealed that it exerts its antibacterial activity by disrupting bacterial membranes. Additionally, it possesses strong biofilm inhibitory and eradication activities as well as significant lipopolysaccharide (LPS)-binding activity. Furthermore, Brevinin-1BW has shown a significant anti-inflammatory effect in LPS-treated RAW264.7 cells. In conclusion, Brevinin-1BW is anticipated to be a promising clinical agent with potent anti-Gram-positive bacterial and anti-inflammatory properties.


Asunto(s)
Lipopolisacáridos , Staphylococcus aureus Resistente a Meticilina , China , Antibacterianos/farmacología , Antiinflamatorios/farmacología , Péptidos Antimicrobianos
14.
Front Vet Sci ; 11: 1368725, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500602

RESUMEN

Japanese encephalitis virus (JEV), a member of the Flaviviridae family and a flavivirus, is known to induce acute encephalitis. Vimentin protein has been identified as a potential receptor for JEV, engaging in interactions with the viral membrane protein. The Fc fragment, an integral constituent of immunoglobulins, plays a crucial role in antigen recognition by dendritic cells (DCs) or phagocytes, leading to subsequent antigen presentation, cytotoxicity, or phagocytosis. In this study, we fused the receptor of JEV vimentin with the Fc fragment of IgG and expressed the resulting vimentin-Fc fusion protein in Escherichia coli. Pull-down experiments demonstrated the binding ability of the vimentin-Fc fusion protein to JEV virion in vitro. Additionally, we conducted inhibition assays at the cellular level, revealing the ability of vimentin-Fc protein suppressing JEV replication, it may be a promising passive immunotherapy agent for JEV. These findings pave the way for potential therapeutic strategies against JEV.

15.
Anal Methods ; 16(9): 1390-1398, 2024 02 29.
Artículo en Inglés | MEDLINE | ID: mdl-38353054

RESUMEN

Accidental ingestion of poisonous mushrooms leading to poisoning is a global issue. The most important and lethal toxin causing mushroom poisoning is α-amanitin, with a lethal dose of about 0.1 mg kg-1. Rapid detection of wild mushrooms before consumption or rapid identification of toxins after poisoning can effectively reduce the occurrence of fatalities. This study established a method for detecting α-amanitin using carbon dots/AuNPs nanoenzymes (D-Glu-CDs/AuNPs) with robust peroxidase-like activity. This nanoenzyme was prepared employing glucose carbon dots and sodium citrate as reducing and stabilizing agents, respectively. It could oxidize the substrate TMB (tetramethylbenzidine) to produce blue o-TMB. When α-amanitin specifically bound to the active site of the nanoenzyme, a resultant decrease was observed in catalytic activity and the absorbance value at 652 nm. The regression equation Y = -0.06083x + 0.9643, with an R2 value of 0.996, was obtained. The limit of detection was determined to be 48.03 ng mL-1, and the recoveries in urine ranged from 91.2% to 97.6%. This method enabled the visualization of α-amanitin, and the whole detection process was completed within 20 min. The approach holds promise for the quantitative and qualitative determination of α-amanitin in urine samples.


Asunto(s)
Agaricales , Nanopartículas del Metal , Alfa-Amanitina , Oro , Carbono , Colorimetría , Agaricales/química
16.
J Am Chem Soc ; 146(9): 6125-6133, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38323980

RESUMEN

Chemical analysis of ions and small organic molecules in liquid samples is crucial for applications in chemistry, biology, environmental sciences, and health monitoring. Mainstream electrochemical and chromatographic techniques often suffer from complex and lengthy sample preparation and testing procedures and require either bulky or expensive instrumentation. Here, we combine triboelectrification and charge transfer on the surface of electrical insulators to demonstrate the concept of triboelectric spectroscopy (TES) for chemical analysis. As a drop of the liquid sample slides along an insulating reclined plane, the local triboelectrification of the surface is recorded, and the charge pattern along the sample trajectory is used to build a fingerprinting of the charge transfer spectroscopy. Chemical information extracted from the charge transfer pattern enables a new nondestructive and ultrafast (<1 s) tool for chemical analysis. TES profiles are unique, and through an automated identification, it is possible to match against standard and hence detect over 30 types of common salts, acids, bases and organic molecules. The qualitative and quantitative accuracies of the TES methodology is close to 93%, and the detection limit is as low as ppb levels. Instruments for TES chemical analysis are portable and can be further miniaturized, opening a path to in situ and rapid chemical detection relying on inexpensive, portable low-tech instrumentation.

17.
Adv Sci (Weinh) ; 11(14): e2308115, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38308181

RESUMEN

Circular RNAs (circRNAs) are a crucial yet relatively unexplored class of transcripts known for their tissue- and cell-type-specific expression patterns. Despite the advances in single-cell and spatial transcriptomics, these technologies face difficulties in effectively profiling circRNAs due to inherent limitations in circRNA sequencing efficiency. To address this gap, a deep learning model, CIRI-deep, is presented for comprehensive prediction of circRNA regulation on diverse types of RNA-seq data. CIRI-deep is trained on an extensive dataset of 25 million high-confidence circRNA regulation events and achieved high performances on both test and leave-out data, ensuring its accuracy in inferring differential events from RNA-seq data. It is demonstrated that CIRI-deep and its adapted version enable various circRNA analyses, including cluster- or region-specific circRNA detection, BSJ ratio map visualization, and trans and cis feature importance evaluation. Collectively, CIRI-deep's adaptability extends to all major types of RNA-seq datasets including single-cell and spatial transcriptomic data, which will undoubtedly broaden the horizons of circRNA research.


Asunto(s)
Aprendizaje Profundo , ARN Circular , ARN Circular/genética , ARN/genética , Transcriptoma/genética , Perfilación de la Expresión Génica
18.
Sci Rep ; 14(1): 1482, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233451

RESUMEN

A total of 40 fiber reinforced polymer (FRP) and polyvinyl chloride (PVC) confined spontaneous combustion gangue coarse-aggregate concrete (SAC) specimens were subjected to axial compression tests and theoretical studies. The main analysis focused on the impact of the replacement rate of spontaneous combustion gangue (SCG), the type of CFRP confinement, and the number of CFRP layers on the axial compression performance of CFRP-PVC confined SAC (CFRP-PVC-SAC). The results show that CFRP-PVC confinement can effectively enhance the axial compressive capacity, axial deformation, and lateral deformation of the components. The increase in strength ranges from 1.68 to 3.48 times, while the increase in strain ranges from 5.21 to 11.98 times. The crack patterns and expansive behavior of the coal gangue concrete under confinement exhibit significant differences compared to ordinary concrete. In addition, based on the framework of the existing FRP-confined plain concrete model, a modified model is established to facilitate prediction of stress-strain relationships for short columns of CFRP-PVC-SAC, with the calculated results in good agreement with experimental values.

19.
Anal Bioanal Chem ; 416(1): 299-311, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37932512

RESUMEN

Methylmercury (MeHg+) is a common form of organic mercury that is substantially more toxic than inorganic mercury and is more likely to accumulate in organisms through biological enrichment. Therefore, developing a method to enable the specific and rapid detection of MeHg+ in seafood is important and remains challenging to accomplish. Herein, a rapid, label-free fluorescence detection method for MeHg+ determination was developed based on SYBR Green I. The detection system implemented "add and measure" detection mode can be completed in 10 min. Under optimal assay conditions, the detection platform showed a linear relationship with the concentration of MeHg+ within 1-50 nM (Y = 8.573x + 42.89, R2 = 0.9928), with a detection limit of 0.3218 nM. The results obtained for competitive substances, such as inorganic mercury ions and anions, show a high specificity of the method. In addition, this method successfully detected MeHg+ in seawater and marine products, with an accompanying spike recovery rate of 96.45-105.1%.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Fluorometría , Agua de Mar
20.
Int J Biol Macromol ; 255: 128085, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37977454

RESUMEN

Rabies has been with humans for a long time, and its special transmission route and almost 100 % lethality rate made it once a nightmare for humans. In this study, by predicting the rabies virus glycoprotein outer membrane region and nucleoprotein B-cell antigenic epitopes, the coding sequence of the predicted highly antigenic polypeptide region obtained was assembled using the eukaryotic expression vector pcDNA3.1(-), and then E. coli was used as the delivery vector. The immunogenicity and protective properties of the vaccine were verified by in vivo and in vitro experiments, which demonstrated that the vaccine could produce antibodies in mice and prolong the survival time of mice exposed to the strong virus without any side effects. This study demonstrated that the preparation of an oral rabies DNA vaccine using food-borne microorganisms as a transport vehicle is feasible and could be a new strategy to eradicate rabies starting with wild animals.


Asunto(s)
Vacunas Antirrábicas , Virus de la Rabia , Rabia , Vacunas de ADN , Humanos , Animales , Ratones , Rabia/prevención & control , Escherichia coli , Anticuerpos Antivirales , Vacunas Antirrábicas/genética , Virus de la Rabia/genética , Epítopos de Linfocito B/genética
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