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1.
Plant Biotechnol J ; 22(5): 1206-1223, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38062934

RESUMO

Rutin, a flavonoid rich in buckwheat, is important for human health and plant resistance to external stresses. The hydrolysis of rutin to quercetin underlies the bitter taste of Tartary buckwheat. In order to identify rutin hydrolysis genes, a 200 genotypes mini-core Tartary buckwheat germplasm resource was re-sequenced with 30-fold coverage depth. By combining the content of the intermediate metabolites of rutin metabolism with genome resequencing data, metabolite genome-wide association analyses (GWAS) eventually identified a glycosyl hydrolase gene FtGH1, which could hydrolyse rutin to quercetin. This function was validated both in Tartary buckwheat overexpression hairy roots and in vitro enzyme activity assays. Mutation of the two key active sites, which were determined by molecular docking and experimentally verified via overexpression in hairy roots and transient expression in tobacco leaves, exhibited abnormal subcellular localization, suggesting functional changes. Sequence analysis revealed that mutation of the FtGH1 promoter in accessions of two haplotypes might be necessary for enzymatic activity. Co-expression analysis and GWAS revealed that FtbHLH165 not only repressed FtGH1 expression, but also increased seed length. This work reveals a potential mechanism behind rutin metabolism, which should provide both theoretical support in the study of flavonoid metabolism and in the molecular breeding of Tartary buckwheat.


Assuntos
Fagopyrum , Rutina , Humanos , Quercetina/metabolismo , Fagopyrum/genética , Fagopyrum/metabolismo , Estudo de Associação Genômica Ampla , Hidrólise , Simulação de Acoplamento Molecular , Multiômica , Flavonoides/metabolismo , Hidrolases/metabolismo
2.
J Magn Reson Imaging ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767272

RESUMO

BACKGROUND: Cognitive impairment is commonly observed in hydrocephalus patients. Ventricular enlargement compresses brain parenchyma, especially the white matter (WM). PURPOSE: To investigate whether the relationship between ventricular dilation and cognitive decline in hydrocephalus patients is mediated by WM alterations. STUDY TYPE: Retrospective. POPULATION: 51 communicating hydrocephalus patients (median age, 54 years), 50 obstructive hydrocephalus patients (median age, 49 years), and 53 control subjects (median age, 50 years). FIELD STRENGTH/SEQUENCE: Diffusion tensors imaging, 3D T1 BRAVO, 3D FIESTA, CUBE T2, and FLAIR sequences at 3T. ASSESSMENT: DTI parameters (skeletonized fractional anisotropy (FA), skeletonized mean diffusivity (MD), and peak width of skeletonized mean diffusivity p(PSMD)) were extracted using FSL software. Global, periventricular, and deep white matter hyperintensity (WMH) volumes, degree of ventricular enlargement (Evans index), and other conventional imaging markers (number of lacunes and perivascular spaces, intracranial and brain volume) were extracted using united imaging intelligence. Cognitive tests included Montreal cognitive assessment (MoCA), clock drawing test (CDT), and vocabulary fluency test (VFT). STATISTICAL TESTS: Multivariable linear regression analysis, mediation analyses, and dominance analysis. P-value <0.05 was considered significant. RESULTS: The degree of ventricular dilation, DTI parameters, and cognitive function scores were interrelated. The skeletonized FA values (ß = -0.0917, 95% confidence interval (CI): -0.205, -0.024) and normalized global WMH volume (ß = -0.0635, 95% CI: -0.13, -0.0005) together mediated 37.2% of the association between Evans index and MoCA. A comparable causal pathway was found for periventricular WMHs but not for deep WMHs. Dominance analysis indicated skeletonized FA values had a greater impact on cognition than WMH volume. The skeletonized FA values also mediated the association between Evans index and CDT (ß = -0.0897, 95% CI: -0.165, -0.026) and VFT (ß = -0.1589, 95% CI: -0.27, -0.083). CONCLUSION: WM alterations were causal mediators between ventricular dilation and cognitive decline in hydrocephalus patients. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 3.

3.
Environ Res ; 216(Pt 2): 114569, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244439

RESUMO

Maghemite (γ-Fe2O3) nanoparticles (MNPs) were functionalized with 3-aminopropyltriethoxysilane (APTES) to give APTES@Fe2O3 (AMNP) which was then reacted with diethylenetriamine-pentaacetic acid (DTPA) to give a nanohybrid DTPA-APTES@Fe2O3 (DAMNP). Nano-isothermal titration calorimetry shows that DTPA complexation with uranyl ions in water is exothermic and has a stoichiometry of two DTPA to three uranyl ions. Density functional theory calculations indicate the possibility of several complexes between DTPA and UO22+ with different stoichiometries. Interactions between uranyl ions and DAMNP functional groups are revealed by X-photoelectron and Fourier transform infrared spectroscopies. Spherical aberration-corrected Scanning Transmission Electron Microscopy visualizes uranium on the particle surface. Adsorbent performance metrics were evaluated by batch adsorption studies under different conditions of pH, initial uranium concentration and contact time, and the results expressed in terms of equilibrium adsorption capacities (qe) and partition coefficients (PC). By either criterion, performance increases from MNP to AMNP to DAMNP, with the maximum uptake at pH 5.5 in all cases: MNP, qe = 63 mg g-1, PC = 127 mg g-1 mM-1; AMNP, qe = 165 mg g-1, PC = 584 mg g-1 mM-1; DAMNP, qe = 249 mg g-1, PC = 2318 mg g-1 mM-1 (at 25 °C; initial U concentration 0.63 mM; 5 mg adsorbent in 10 mL of solution; contact time, 3 h). The pH maximum is related to the predominance of mono- and di-cationic uranium species. Uptake by DAMNPs follows a pseudo-first-order or pseudo-second-order kinetic model and fits a variety of adsorption models. The maximum adsorption capacity for DAMNPs is higher than for other functionalized magnetic nanohybrids. This adsorbent can be regenerated and recycled for at least 10 cycles with less than 10% loss in activity, and shows high selectivity. These findings suggest that DAMNP could be a promising adsorbent for the recovery of uranium from nuclear wastewaters.


Assuntos
Urânio , Águas Residuárias , Adsorção , Águas Residuárias/química , Urânio/análise , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Cátions , Fenômenos Magnéticos , Nanopartículas Magnéticas de Óxido de Ferro , Ácido Pentético , Concentração de Íons de Hidrogênio
4.
Int J Mol Sci ; 24(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37445761

RESUMO

Bacterial conjugation constitutes a major horizontal gene transfer mechanism for the dissemination of antibiotic-resistant genes (ARGs) among human pathogens. The spread of ARGs can be halted or diminished by interfering with the conjugation process. In this study, we explored the possibility of using an rbsB gene as a single target to inhibit plasmid-mediated horizontal gene transfer in Escherichia coli by CRISPR interference (CRISPRi) system. Three single-guide RNAs (sgRNAs) were designed to target the rbsB gene. The transcriptional levels of the rbsB gene, the conjugation-related genes, and the conjugation efficiency in the CRISPRi strain were tested. We further explored the effect of the repressed expression of the rbsB gene on the quorum sensing (QS) system and biofilm formation. The results showed that the constructed CRISPRi system was effective in repressing the transcriptional level of the rbsB gene at a rate of 66.4%. The repressed expression of the rbsB gene resulted in the reduced conjugation rate of RP4 plasmid by 88.7%, which significantly inhibited the expression of the conjugation-related genes (trbBp, trfAp, traF and traJ) and increased the global regulator genes (korA, korB and trbA). The repressed rbsB gene expression reduced the depletion of autoinducer 2 signals (AI-2) by 12.8% and biofilm formation by a rate of 68.2%. The results of this study indicated the rbsB gene could be used as a universal target for the inhibition of conjugation. The constructed conjugative CRISPRi system has the potential to be used in ARG high-risk areas.


Assuntos
Escherichia coli , RNA Guia de Sistemas CRISPR-Cas , Humanos , Escherichia coli/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Conjugação Genética
5.
Phys Rev Lett ; 129(26): 261801, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36608202

RESUMO

We propose using trapped electrons as high-Q resonators for detecting meV dark photon dark matter. When the rest energy of the dark photon matches the energy splitting of the two lowest cyclotron levels, the first excited state of the electron cyclotron will be resonantly excited. A proof-of-principle measurement, carried out with one electron, demonstrates that the method is background free over a 7.4 day search. It sets a limit on dark photon dark matter at 148 GHz (0.6 meV) that is around 75 times better than previous constraints. Dark photon dark matter in the 0.1-1 meV mass range (20-200 GHz) could likely be detected at a similar sensitivity in an apparatus designed for dark photon detection.

6.
J Appl Microbiol ; 132(4): 3111-3124, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35061923

RESUMO

AIM: To understand how beneficial bacteria assist chilli plants (Capsicum annuum) in defence against biotrophic or hemibiotrophic pathogens. METHOD AND RESULTS: We quantified marker genes of plant defence pathways in Phytophthora capsici-infected chilli pepper treated with anti-oomycete plant growth-promoting rhizobacteria, Bacillus amyloliquefaciens, Bacillus velezensis and Acinetobacter sp. Plants displayed strong resistance, and the pathogen load in the roots was significantly lower in infected plants treated with bacterial biocontrol agents at all time points tested (1, 2 and 7 days after pathogen inoculation, p < 0.05). Gene expression profiling revealed that P. capsici infection in the absence of beneficial bacteria led to the upregulation of a wide array of defence genes. The addition of biocontrol bacteria modulated defence by further enhancing genes involved in programmed cell death, such as CaLOX1, CaPAL1, CaChitIV and CaPTI1, while suppressing others CaLRR1, a negative regulator of cell death. CONCLUSIONS: Our results suggest that the bacteria exerted a combined effect by directly antagonizing the pathogen and enhancing the expression of key plant defence genes, including those involved in cell death, causing resistance at early stages of infection by this hemibiotrophic pathogen.


Assuntos
Capsicum , Phytophthora , Apoptose , Bactérias , Capsicum/genética , Capsicum/microbiologia , Phytophthora/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Rizosfera
7.
Ecotoxicol Environ Saf ; 244: 114024, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36057202

RESUMO

Excessive salt intake can induce a variety of diseases, such as hypertension, cardiovascular disease, kidney disease and so on,it is also one of the factors promoting bone resorption. The mechanism of osteoporosis-induced exacerbations of high salt diet is not well-defined. In this study, we used ovariectomized 6-month-old Sprague Dawley rats to construct a high bone turnover model, and then administrated with high sodium chloride diet (2.0% w/w NaCl, 8.0% w/w NaCl) for 12 weeks to observe the effect of high salt diet on bone metabolism. The results showed that high salt diet could lead to the destruction of bone microstructure, promote the excretion of urinary calcium and phosphorus and accelerate the bone turnover, as well as cause the pathologic structural abnormalities in renal tubular. At the same time, it was accompanied by the up-regulated expression of the epithelial sodium channel (ENaCα), voltage-gated chloride channels (ClC)- 3 and the down-regulated expression of Na-Cl cotransporter (NCC), sodium calcium exchanger (NCX1) in femoral tissue and renal tubules. These findings confirm that high salt diet can destroy the microstructure of bone by increasing bone resorption and affect some ion channels of bone tissue and renal tubule in ovariectomized rats.


Assuntos
Reabsorção Óssea , Cloreto de Sódio na Dieta , Animais , Reabsorção Óssea/metabolismo , Osso e Ossos/metabolismo , Cálcio/metabolismo , Canais de Cloreto/metabolismo , Canais de Cloreto/farmacologia , Dieta , Canais Epiteliais de Sódio/metabolismo , Rim , Fósforo/metabolismo , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio/farmacologia , Trocador de Sódio e Cálcio/metabolismo , Trocador de Sódio e Cálcio/farmacologia , Membro 3 da Família 12 de Carreador de Soluto/metabolismo
8.
Langmuir ; 37(37): 10994-11007, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34499835

RESUMO

Ca-modified Fe3O4 nanoparticles encapsulated in humic acid (HA-Ca/Fe3O4) were produced using a co-precipitation method. Furthermore, the adsorption performance of HA-Ca/Fe3O4 as well as the effect of coexisting ions and mechanisms were evaluated. A good description of the adsorption process was given using pseudo-second-order kinetic and Langmuir models. The adsorption capacities of HA-Ca/Fe3O4 for Pb2+, Cu2+, and Cd2+ were 208.33, 98.33, and 99.01 mg g-1, respectively. The 0.02-0.1 times concentrations in alkali and alkaline-earth metals promoted Pb2+ and Cd2+ adsorption; however, any concentration of alkali and alkaline-earth metals inhibited Cu2+-ion adsorption, probably owing to the differences in ionic radii between the interfering and heavy-metal ions. Pb2+, Cu2+, and Cd2+ removal using HA-Ca/Fe3O4 occurred via ion exchange, complexation of O-containing functional groups, mineral precipitation, and π-electron coordination. A method was proposed to calculate the contribution of these mechanisms to the adsorption process. In practice, HA-Ca/Fe3O4 can remove 99% Pb2+ and 91% Cu2+ and Cd2+ from real wastewater samples. Following five adsorption-desorption cycles, HA-Ca/Fe3O4 adsorption capacity did not change significantly. The aforementioned results indicated that HA-Ca/Fe3O4 presented a good potential in removing heavy metals in wastewater.


Assuntos
Metais Pesados , Nanopartículas , Poluentes Químicos da Água , Adsorção , Cálcio , Substâncias Húmicas , Águas Residuárias , Poluentes Químicos da Água/análise
9.
Angew Chem Int Ed Engl ; 59(12): 4763-4769, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31881117

RESUMO

Metal-organic frameworks (MOFs) are promising materials with fascinating properties. Their widespread applications are sometimes hindered by the intrinsic instability of frameworks. However, this instability of MOFs can also be exploited for useful purposes. Herein, we report the use of MOFs as metal ion precursors for constructing functional nanocomposites by utilizing the instability of MOFs. The heterogeneous growth process of nanostructures on substrates involves the release of metal ions, nucleation on substrates, and formation of a covering structure. Specifically, the synthesized CoS with carbon nanotubes as substrates display enhanced performance in a lithium-ion battery. Such strategy not only presents a new way for exploiting the instability of MOFs but also supplies a prospect for designing versatile functional nanocomposites.

10.
J Cell Physiol ; 234(10): 16838-16846, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30786010

RESUMO

Subjective cognitive decline (SCD) is frequently reported in diabetic patients. Diabetes mellitus (DM) is associated with changes in the microstructure of the brain arise in diabetic patients, including changes in gray matter volume (GMV). However, the underlying mechanisms of changes in GMV in DM patients with cognitive impairment remain uncertain. Here, we present an overview of amyloid-ß-dependent cognitive impairment in DM patients with SCD. Moreover, we review the evolving insights from studies on the GMV changes in GMV and cognitive dysfunction to which provide the mechanisms of cognitive impairment in T2DM. Ultimately, the novel structural magnetic resonance imaging (MRI) protocol was used for detecting neuroimaging biomarkers that can predict the clinical outcomes in diabetic patients with SCD. A reliable MRI protocol would be helpful to detect neurobiomarkers, and to understand the pathological mechanisms of preclinical cognitive impairment in diabetic patients.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/patologia , Diabetes Mellitus , Imageamento por Ressonância Magnética , Biomarcadores , Humanos
11.
Neurol Sci ; 40(6): 1105-1110, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30771023

RESUMO

Traumatic brain injury (TBI) can cause non-neurological injuries to other organs such as the intestine. Newer studies have shown that paracellular hyperpermeability is the basis of intestinal barrier dysfunction following TBI. Ischemia-reperfusion injury, inflammatory response, abnormal release of neurotransmitters and hormones, and malnutrition contribute to TBI-induced intestinal barrier dysfunction. Several interventions that may protect intestinal barrier function and promote the recovery of TBI have been proposed, but relevant studies are still limited. This review is to clarify the established mechanisms of intestinal barrier dysfunction following TBI and to describe the possible strategies to reduce or prevent intestinal barrier dysfunction.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Enteropatias/fisiopatologia , Mucosa Intestinal/fisiopatologia , Animais , Lesões Encefálicas Traumáticas/complicações , Células Epiteliais/fisiologia , Humanos , Enteropatias/etiologia
12.
J Food Sci Technol ; 56(2): 674-682, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30906025

RESUMO

The objective of this study was to evaluate the effect of operating parameters including milling weight (MW; 10, 95, 220, 345, 430 g), filling ratio (FR; 1, 1.4, 2, 2.6, 3) and milling duration (MD; 6, 30, 65, 100, 124 s) on head rice yield (HRY), whiteness index (WI) and specific energy consumption (Es). The experiments were conducted based on a vertical circulation mill employing a 5 level, 3 parameters CCD design and operating parameters were optimized using response surface methodology. During the processing, MW and MD had significant negative effects on HRY. On the contrary, they both had significant positive effects on WI. All the three parameters had a significant effect on Es Taking HRY, WI, Es as the evaluative index and degree of milling, temperature rise of milled rice as the restrictive index, the best combination of operating parameters was obtained, namely MW of 345 g, FR of 2.6 and MD of 30 s. The Pearson correlation coefficients between all the milling qualities were analyzed. Results showed that the temperature rise as an easy measurement index was highly correlated with the other qualities. The regression models between temperature rise and the other milling quality indices can assist in evaluating the quality of milled rice quickly and quantifiably.

13.
Biosens Bioelectron ; 250: 116048, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38266618

RESUMO

Real-time monitoring of nitric oxide (NO) is of great importance in diagnosing the physiological functions of neurotransmission, cardiovascular, and immune systems. This study reports the carbon nanotube-interconnected ruthenium phthalocyanine nanoparticle nanocomposite and its applicability in construction of an electrochemical platform, which could real-time detect NO released from the vascular endothelial barrier (VEB) model in cell culture medium. The nanocomposite exhibits regular morphology, uniform particle size, and excellent electro-catalytic activity to electrochemical oxidation of NO. Under optimal conditions, the electrochemical device has high sensitivity (0.871 µA µM-1) and can selectively detect NO down to the concentration of 6 × 10-10 M. The human brain microvascular endothelial cells were cultured onto the Transwell support to construct the VEB model. Upon stimulated by L-arginine, NO produced by the VEB diffuses into the bottom chamber of the Transwell, and is real-time monitored by the electrochemical device. Moreover, evaluation of the NO inhibition by drug is realized using the electrochemical device-Transwell platform. This simple and sensitive platform would be of great interesting for evaluating the endothelial function or its pathological states, and screening the related drugs or chemicals.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Nanotubos de Carbono , Compostos Organometálicos , Humanos , Técnicas Eletroquímicas , Óxido Nítrico , Células Endoteliais
14.
Acta Pharm Sin B ; 14(7): 3049-3067, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39027246

RESUMO

The mucosal barrier is crucial for intestinal homeostasis, and goblet cells are essential for maintaining the mucosal barrier integrity. The proviral integration site for Moloney murine leukemia virus-1 (PIM1) kinase regulates multiple cellular functions, but its role in intestinal homeostasis during colitis is unknown. Here, we demonstrate that PIM1 is prominently elevated in the colonic epithelia of both ulcerative colitis patients and murine models, in the presence of intestinal microbiota. Epithelial PIM1 leads to decreased goblet cells, thus impairing resistance to colitis and colitis-associated colorectal cancer (CAC) in mice. Mechanistically, PIM1 modulates goblet cell differentiation through the Wnt and Notch signaling pathways. Interestingly, PIM1 interacts with histone deacetylase 2 (HDAC2) and downregulates its level via phosphorylation, thereby altering the epigenetic profiles of Wnt signaling pathway genes. Collectively, these findings investigate the unknown function of the PIM1-HDAC2 axis in goblet cell differentiation and ulcerative colitis/CAC pathogenesis, which points to the potential for PIM1-targeted therapies of ulcerative colitis and CAC.

15.
Foods ; 12(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37174402

RESUMO

Excessive milling of rice kernels will result in nutrient loss and grain waste. To avoid grain waste, multibreak milling systems have been widely used in large-scale commercial rice mills. However, there is still no reasonable breakpoint planning method to guide the multibreak milling process. To construct a reasonable multibreak milling system, in this research, taking rice milling, a typical heterogeneous cereal-kernel milling process, as an example, the multivariate analysis method was used to comprehensively analyze the characteristic changes of milled rice during the whole milling process. A breakpoint planning method was established, including planning the number of breakpoints, determining the degree of milling or milling time corresponding to each breakpoint, and estimating the actual breakpoint to which the milled rice belongs. The verification results showed the rationality and high accuracy of the planning method. The presented work will help operators to plan the multibreak milling system of rice efficiently and objectively so as to significantly improve the commercial value of milled rice.

16.
Biosens Bioelectron ; 230: 115236, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36989662

RESUMO

This work demonstrates an organic electrochemical transistor (OECT) immuno-sensor with a detection limit down to fg mL-1. The OECT device transforms the antibody-antigen interaction signal by using the zeolitic imidazolate framework-enzyme-metal polyphenol network nanoprobe, which can produce electro-active substance (H2O2) through the enzyme-catalytic reaction. The produced H2O2 is subsequently electrochemically oxidized at the platinum loaded CeO2 nanosphere-carbon nanotube modified gate electrode, resulting in an amplified current response of the transistor device. This immuno-sensor realizes the selective determination of vascular endothelial growth factor 165 (VEGF165) down to the concentration of 13.6 fg mL-1. It also shows good applicable capacity for determining the VEGF165 that human brain microvascular endothelial cells and U251 human glioblastomas cells secreted in the cell culture medium. The ultrahigh sensitivity of the immuno-sensor is derived from excellent performances of the nanoprobe for enzyme loading and the OECT device for H2O2 detection. This work may provide a general way to fabricate the OECT immuno-sensing device with high performances.


Assuntos
Técnicas Biossensoriais , Nanosferas , Nanotubos de Carbono , Zeolitas , Humanos , Fator A de Crescimento do Endotélio Vascular , Platina , Polifenóis , Zeolitas/química , Peróxido de Hidrogênio , Células Endoteliais , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos
17.
Biosens Bioelectron ; 238: 115593, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597283

RESUMO

In view of the importance of quantification of neuron-specific enolase (NSE), an electrochemical NSE immunosensor was developed. The sandwich voltammetric immunosensor utilized vinyl-functionalized crystalline covalent organic framework (COFTAPT-Dva) modified electrode to load lots of Ab1 via thiol-ene "click" reaction as matrix. A crystalline cationic EB-COF:Br was used to load Au nanoparticles (AuNPs) and H3[PMo12O40] (PMo12) as immunoprobe. The AuNPs with the size of about 30 nm were firstly grown on EB-COF:Br and then a large number of electroactive PMo12 were uniformly assembled on AuNPs/EB-COF:Br via ion exchanging reaction. The AuNPs not only facilitated the bonding of Ab2 based on Au-S bond, but also improved performance of Ab2/AuNPs/EB-COF:PMo12 immunoprobe. The sensitivity of sandwich electrochemical immunosensor could be primarily amplified based on loaded abundant PMo12. Secondary sensitivity amplification of immunosensor could be achieved by using PMo12 to catalyze ascorbic acid. The linear range of sandwich voltammetric immunosensor based on current change of differential pulse voltammetry is 500 ± 36 fg mL-1 - 100 ± 8 ng mL-1. Thanks to the dual sensitivity amplification strategy, the sensitivity is as high as 54.06 ± 3.2 µA cm-2/lg(cNSE/ng mL-1), and the detection limit is as low as 166 ± 10.8 fg mL-1. It proves that it is completely feasible to amplify sensitivity of sandwich voltammetric immunosensors using polyoxometalate-COF and its catalytic substrate.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ácido Ascórbico , Ouro , Imunoensaio , Fosfopiruvato Hidratase , Catálise
18.
Int J Biol Macromol ; 253(Pt 1): 126616, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652339

RESUMO

A feasible approach to enhance the antimicrobial efficacy of ε-polylysine (PL) in applications is to form delivery complexes with delicate structures and good dispersion properties. This work aims to study the multiscale structures, properties and interactions, and edible coating applications of the electrostatic complex formed by PL and soy protein isolate (SPI). When the mass ratio of SPI to PL (SE) was between 5 and 15, especially 11, microscale solid-liquid phase separation occurred in the system due to the small absolute zeta potential. When the SE was in the range of 15-20, the system formed a stable nanoscale suspension, the average particle size and zeta potential were 191 nm and -20 mV, respectively. The physicochemical properties of the complexes were investigated including the colloidal properties, spectroscopy and interactions analysis, viscosity, contact angle, and antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Penicillium expansum. Finally, the in vivo application on citrus demonstrated that the nanoscale PL/SPI electrostatic complex (SE = 20) as functional coatings has both barrier and antimicrobial activities. The study provides a novel application strategy for PL and nanoscale electrostatic complexes as postharvest coatings.


Assuntos
Anti-Infecciosos , Citrus , Filmes Comestíveis , Polilisina/farmacologia , Polilisina/química , Proteínas de Soja , Eletricidade Estática , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Escherichia coli
19.
Regen Biomater ; 10: rbad071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719928

RESUMO

The most common socioeconomic healthcare issues in clinical are burns, surgical incisions and other skin injuries. Skin lesion healing can be achieved with nanomedicines and other drug application techniques. This study developed a nano-spray based on cross-linked amorphous calcium peroxide (CaO2) nanoparticles of polyacrylic acid (PAA) for treating skin wounds (PAA-CaO2 nanoparticles). CaO2 serves as a 'drug' precursor, steadily and continuously releasing calcium ions (Ca2+) and hydrogen peroxide (H2O2) under mildly acidic conditions, while PAA-CaO2 nanoparticles exhibited good spray behavior in aqueous form. Tests demonstrated that PAA-CaO2 nanoparticles exhibited low cytotoxicity and allowed L929 cells proliferation and migration in vitro. The effectiveness of PAA-CaO2 nanoparticles in promoting wound healing and inhibiting bacterial growth in vivo was assessed in SD rats using full-thickness skin defect and Staphylococcus aureus (S.aureus)-infected wound models based thereon. The results revealed that PAA-CaO2 nanoparticles demonstrated significant advantages in both aspects. Notably, the infected rats' skin defects healed in 12 days. The benefits are linked to the functional role of Ca2+ coalesces with H2O2 as known antibacterial and healing-promoted agents. Therefore, we developed nanoscale PAA-CaO2 sprays to prevent bacterial development and heal skin lesions.

20.
Autophagy ; 19(10): 2702-2718, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37312409

RESUMO

HSPA8 (heat shock protein family A (Hsp70) member 8) plays a significant role in the autophagic degradation of proteins, however, its effect on protein stabilization and anti-bacterial autophagy remains unknown. Here, it is discovered that HSPA8, as a binding partner of RHOB and BECN1, induce autophagy for intracellular bacteria clearance. Using its NBD and LID domains, HSPA8 physically binds to RHOB residues 1-42 and 89-118 as well as to BECN1 ECD domain, preventing RHOB and BECN1 degradation. Intriguingly, HSPA8 contains predicted intrinsically disordered regions (IDRs), and drives liquid-liquid phase separation (LLPS) to concentrate RHOB and BECN1 into HSPA8-formed liquid-phase droplets, resulting in improved RHOB and BECN1 interactions. Our study reveals a novel role and mechanism of HSPA8 in modulating anti-bacterial autophagy, and highlights the effect of LLPS-related HSPA8-RHOB-BECN1 complex on enhancing protein interaction and stabilization, which improves the understanding of autophagy-mediated defense against bacteria.


Assuntos
Autofagia
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