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1.
Talanta ; 270: 125534, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38091743

ABSTRACT

Simultaneous detection of active and inactive proteases is clinically meaningful for improving diagnostic specificity. In this work, we reported an electrochemical method for simultaneous immunoassays of active and total proteases. Magnetic beads (MBs) were used as the solid supports for immobilization of capture antibodies and enrichment of targets. For the detection of active protease, the proteolytic-reaction-based analysis was carried out by the generation of Cu2+-binding peptide, in which a label-free peptide was used as the proteolytic substrate. The redox potential of the resulting peptide-Cu2+ complex was intrinsically distinguished from that of free Cu2+, thus allowing the "signal-on" detection of active protease. For the immunoassay of total protease in a sandwich-like format, electroactive metal-organic frameworks (Cu-MOFs) were used as the signal tags. The captured Cu-MOFs could directly produce a well-defined electrochemical signal from the reduction of Cu2+ ions. The analytical performances of the immunoplatform were evaluated by determining the model analytes of free and total prostate-specific antigen (fPSA and tPSA) in buffer and serum. The detection limits were found to be 0.3 pM for fPSA and 2 pM for tPSA. This work proposed a new strategy for simultaneous detection of active and total proteases, which should be evaluable for clinical diagnosis and treatment of protease-relative diseases.


Subject(s)
Biosensing Techniques , Metal-Organic Frameworks , Male , Humans , Prostate-Specific Antigen/analysis , Immunoassay/methods , Antibodies , Peptides , Electrochemical Techniques/methods , Biosensing Techniques/methods , Limit of Detection
2.
Anal Chim Acta ; 1284: 341994, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37996157

ABSTRACT

BACKGROUND: Monitoring peptide ligase activity is of great significance for biological research, medical diagnosis, and drug discovery. The current methods for the detection of peptide ligases suffer from the limitations of high background signal, elaborate design of substrate, and high reversibility of ligation reaction. In this work, we proposed a simple and sensitive method for ligase detection with reducing ligation reversibility on the basis of aggregation-induced emission (AIE) mechanism. RESULTS: The peptide probes labeled with AIE luminogens (AIEgens) were water-soluble and emitted weak fluorescence. After ligation reaction, the enzymatic products with AIEgens showed high hydrophobicity and could readily assembly into aggregates, thus lighting up the fluorescence. More interestingly, the formation of aggregates pushed the equilibrium to the generation of the desired ligation products, thus improving the catalytic efficiency by driving the reaction towards completion. The ligation reaction conversion rate (>80 %) is significantly higher than that without blocking the reversibility with additional treatment. With sortase A (SrtA) as the analyte example, the detection limit of this method was found to be 0.01 nM with a linear range of 0-50 nM. The system was applied to evaluate the inhibition efficiency of berberine chloride and quercetin and determine the activity of SrtA in serum, lysate and Staphylococcus aureus with satisfactory results. SIGNIFICANCE: This study indicated that the ligation efficiency and detection sensitivity can be improved by reducing ligation reversibility through AIE phenomenon. The proposed strategy could be used for the detection of other peptide ligases by adopting sequence-specific peptide substrates.


Subject(s)
Ligases , Peptides , Fluorescence , Hydrophobic and Hydrophilic Interactions
3.
Theranostics ; 13(13): 4304-4315, 2023.
Article in English | MEDLINE | ID: mdl-37649594

ABSTRACT

Glioblastoma multiforme (GBM) is the most common and lethal type of adult brain cancer. Current GBM standard of care, including radiotherapy, often ends up with cancer recurrence, resulting in limited long-term survival benefits for GBM patients. Immunotherapy, such as immune checkpoint blockade (ICB), has thus far shown limited clinical benefit for GBM patients. Therapeutic vaccines hold great potential to elicit anti-cancer adaptive immunity, which can be synergistically combined with ICB and radiotherapy. Peptide vaccines are attractive for their ease of manufacturing and stability, but their therapeutic efficacy has been limited due to poor vaccine co-delivery and the limited ability of monovalent antigen vaccines to prevent tumor immune evasion. To address these challenges, here, we report GBM radioimmunotherapy that combines radiotherapy, ICB, and multivalent lymph-node-targeting adjuvant/antigen-codelivering albumin-binding vaccines (AAco-AlbiVax). Specifically, to codeliver peptide neoantigens and adjuvant CpG to lymph nodes (LNs), we developed AAco-AlbiVax based on a Y-shaped DNA scaffold that was site-specifically conjugated with CpG, peptide neoantigens, and albumin-binding maleimide-modified Evans blue derivative (MEB). As a result, these vaccines elicited antitumor immunity including neoantigen-specific CD8+ T cell responses in mice. In orthotopic GBM mice, the combination of AAco-AlbiVax, ICB, and fractionated radiation enhanced GBM therapeutic efficacy. However, radioimmunotherapy only trended more efficacious over radiotherapy alone. Taken together, these studies underscore the great potential of radioimmunotherapy for GBM, and future optimization of treatment dosing and scheduling would improve the therapeutic efficacy.


Subject(s)
Glioblastoma , Vaccines , Animals , Mice , Glioblastoma/radiotherapy , Radioimmunotherapy , Neoplasm Recurrence, Local , Adjuvants, Immunologic , Adjuvants, Pharmaceutic , Albumins , Lymph Nodes
4.
Sci Adv ; 9(28): eade6257, 2023 07 14.
Article in English | MEDLINE | ID: mdl-37450588

ABSTRACT

Current cancer immunotherapy [e.g., immune checkpoint blockade (ICB)] only benefits small subsets of patients, largely due to immunosuppressive tumor microenvironment (TME). In situ tumor vaccination can reduce TME immunosuppression and thereby improve cancer immunotherapy. Here, we present single-dose injectable (nanovaccines + ICBs)-in-hydrogel (NvIH) for robust immunotherapy of large tumors with abscopal effect. NvIH is thermo-responsive hydrogel co-encapsulated with ICB antibodies and novel polymeric nanoparticles loaded with three immunostimulatory agonists for Toll-like receptors 7/8/9 (TLR7/8/9) and stimulator of interferon genes (STING). Upon in situ tumor vaccination, NvIH undergoes rapid sol-to-gel transformation, prolongs tumor retention, sustains the release of immunotherapeutics, and reduces acute systemic inflammation. In multiple poorly immunogenic tumor models, single-dose NvIH reduces multitier TME immunosuppression, elicits potent TME and systemic innate and adaptive antitumor immunity with memory, and regresses both local (vaccinated) and distant large tumors with abscopal effect, including distant orthotopic glioblastoma. Overall, NvIH holds great potential for tumor immunotherapy.


Subject(s)
Hydrogels , Neoplasms , Humans , Cell Line, Tumor , Immunotherapy , Immunosuppression Therapy , Neoplasms/therapy , Adaptive Immunity , Tumor Microenvironment
5.
BMC Plant Biol ; 23(1): 288, 2023 May 30.
Article in English | MEDLINE | ID: mdl-37254042

ABSTRACT

BACKGROUND: Plants in the genus Artemisia are rich in active ingredients and specialized metabolites. Many of these compounds, especially flavonoids, have potential medicinal and nutritional applications, and are of growing interest to scientists due to their wide range of pharmacological and biological activities. Artemisia cultivars are commonly used as raw materials for medicine, food, and moxibustion in China. However, most of the metabolites produced by Artemisia species have not been identified, and few studies have addressed differences in active compounds between species and cultivars. RESULTS: We here investigated two Artemisia cultivars, 'Nanyangshiyong' (NYSY) and 'Nanyangyaoyong' (NYYY), which are commonly used in foods and moxibustion, respectively. NYSY and NYYY were confirmed to be Artemisia argyi cultivars. Total flavonoids contents and antioxidant activities were higher in NYYY than in NYSY. A total of 882 metabolites were identified in the samples; most of the potentially medicinally active compounds, especially flavonoids (e.g., flavone, flavonol, isoflavone, and anthocyanin), were up-regulated in NYYY compared to NYSY. Furthermore, most of the genes related to flavonoids biosynthesis were up-regulated in NYYY. Correlation analysis was used to identify putative members of transcription factor families that may regulate genes encoding key flavonoids biosynthesis enzymes. CONCLUSIONS: We found that the antioxidant activities and flavonoids contents significantly varied between two Artemisia cultivars of the same species. We also uncovered metabolomic and transcriptomic evidence of the molecular phenomena underlying those differences in flavonoids contents between the two Artemisia cultivars. This study provides a wealth of data for future utilization and improvements of Artemisia cultivars, and highlights a need to study the specific metabolite profiles of plants that are used in foods and medicines.


Subject(s)
Artemisia , Artemisia/genetics , Artemisia/metabolism , Flavonoids/metabolism , Transcriptome , Antioxidants/metabolism , Gene Expression Profiling
6.
Talanta ; 253: 123597, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-35710468

ABSTRACT

The general electrochemical biosensors for telomerase detection require the immobilization of primers on the electrode surface for telomeric extension and hybridization reactions. However, immobilization of primers may suffer from the challenges of hindrance effect and configuration freedom, thus reducing the extension and hybridization efficiency. Herein, we developed a sensitive electrochemical biosensor for telomerase detection by integration of homogeneous extension and hybridization reactions and surface-tethered detection. In the presence of telomerase, the biotinylated primer (bio-primer) was efficiently elongated with telomeric repeats of (TTAGGG)n at the 3' end in solution. Then, the extension product (bio-DNA) was hybridized with the signal probe DNA modified on the surface of ferrocene (Fc)-capped gold nanoparticle (AuNP). The bio-DNA/DNA/Fc-AuNP hybrids were then tethered by streptavidin-modified electrodes through the specific avidin-biotin interactions, thus producing strong electrochemical signals from the oxidation of Fc tags. The biosensor was successfully used to determine telomerase in HeLa cells and monitor the inhibition efficiency of inhibitor. A wide linear range for the detection of telomerase extracted from HeLa cells was attained. This method has great potential in clinical diagnosis and anti-cancer drug development, and should be beneficial for the fabrication of novel biosensors by integration of homogeneous catalysis and hybridization reactions.


Subject(s)
Metal Nanoparticles , Telomerase , Humans , Gold , HeLa Cells , DNA
7.
Int J Ophthalmol ; 15(9): 1423-1430, 2022.
Article in English | MEDLINE | ID: mdl-36124184

ABSTRACT

AIM: To identify potential mutations and elucidate the clinical findings of male patients and female carriers of X-linked retinitis pigmentosa (XLRP) in a Chinese family. METHODS: A four generation pedigree was collected that consisted of 20 individuals. Genomic DNA was extracted from peripheral blood, and then the target fragments were amplified by PCR and sequenced directly. In addition, all affected patients and female carriers underwent comprehensively ophthalmic evaluation. RESULTS: A novel mutation c.2865G>A p.W955X in RPGR gene was identified of this family, including four affected individuals and eight carriers. All male patients, aging from 7 to 31y, tended to have more various, even potentially deleterious clinical features of RP. At the same time, individuals with heterozygous mutations (carriers) manifested a wide spectrum of clinical features. Herein, only two male patients and three female carriers manifested pathological myopia (PM). Among the female carriers, half of subjects who harbor poor visual acuity suffered esotropia or exotropia. Additionally, 16.7% and 66.7% of carriers had abnormal electroretinogram (ERG) and fundus, respectively. CONCLUSION: In this study, a novel mutation of the RPGR gene is identified, which broadens the spectrum of RPGR mutations, and elaborates the relationship between genotype and phenotype.

8.
Front Psychol ; 13: 949673, 2022.
Article in English | MEDLINE | ID: mdl-36072040

ABSTRACT

The notion of teacher identity has gained momentum in second language (L2) teacher education in the past decade. However, the research into Chinese as a Foreign Language (CFL) teacher identity has yet to receive more attention. The study employed a narrative inquiry to explore a native Chinese CFL in-service teacher's identity negotiation and transformation within an international teacher education program. Self-reported narrative accounts, including multiple in-depth interviews and once-a-term reflective journals, were complemented by field notes and program documents. This data captured how the participant teacher negotiated internally with self and externally with the new environment to pursue professional growth. Mezirow's transformative learning theory was used to reveal the cognitive trajectory of the participant's teacher identity transformation with critical reflection as the central stage. Further, guided by Eteläpelto et al.'s framework of professional agency, the study also unraveled multiple external and internal influences on the transformational trajectory. The findings confirmed the value of integrating these two theoretical perspectives to explore language teacher identity development and offer insights into L2 teacher education practices focusing on teacher identity development.

9.
Comput Math Methods Med ; 2022: 8739551, 2022.
Article in English | MEDLINE | ID: mdl-35281951

ABSTRACT

Objectives: The article is aimed at investigating the suture effect of absorbable suture in strabismus correction and the advantage of Watson care theory. Methods: 148 children with strabismus were enrolled in this study and divided into two groups. The control group received routine nursing, and on this basis, the observation group was given Watson care theory nursing and eye muscle suture with absorbable sutures. The degree of cooperation (induction compliance checklist (ICC) score), negative emotion (modified Yale preoperative anxiety scale (m-YAPS) score), pain (face pain scale (FPS) score), quality of nursing management, parents' satisfaction, clinical efficacy, and adverse reactions were compared. Results: After nursing and surgical treatment, all children's strabismus symptoms were improved, and the improvement of strabismus and visual function in the observation group was more obvious. Watson care nursing can effectively improve the nursing management quality, parents' satisfaction, children's negative emotions, and treatment compliance. Conclusions: As a result, Watson care theory nursing is of great significance for improving the relationship between nurses and patients and building a harmonious hospital.


Subject(s)
Nursing Theory , Strabismus/nursing , Strabismus/surgery , Sutures , Child , Child, Preschool , Computational Biology , Female , Humans , Male , Postoperative Complications/etiology , Quality of Health Care , Strabismus/physiopathology , Suture Techniques/nursing
10.
Insects ; 13(1)2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35055939

ABSTRACT

The relative quantification of gene expression is mainly achieved through reverse transcription-quantitative PCR (qRT-PCR); however, its reliability and precision rely on proper data normalization using one or more optimal reference genes. Hyphantria cunea (Drury) has been an invasive pest of forest trees, ornamental plants, and fruit trees in China for many years. Currently, the molecular physiological role of reference genes in H. cunea is unclear, which hinders functional gene study. Therefore, eight common reference genes, RPS26, RPL13, UBI, AK, RPS15, EIF4A, ß-actin, α-tub, were selected to evaluate levels of gene expression stability when subjected to varied experimental conditions, including developmental stage and gender, different tissues, larvae reared on different hosts and different larval density. The geNorm, BestKeeper, ΔCt method, and NormFinder statistical algorithms were used to normalize gene transcription data. Furthermore, the stability/suitability of these candidates was ranked overall by RefFinder. This study provides a comprehensive evaluation of reference genes in H. cunea and could help select reference genes for other Lepidoptera species.

11.
Transl Pediatr ; 10(9): 2335-2346, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34733674

ABSTRACT

BACKGROUND: After strabismus surgery, the local swelling of conjunctival wound will affect the uniform distribution of tears on the ocular surface, and the inflammatory reaction will affect the stability of tear film, which will easily lead to iatrogenic dry eye. This study aimed to investigate the effect of vitamin A palmitate (VAP) eye gel application in dry eye and the advantages of Watson's theory of caring. METHODS: Two hundred and forty children with dry eye after strabismus surgery treated in our hospital from September 2018 to September 2020 were selected as the study subjects, and were randomly divided into control group and observation group according to the allocation ratio of 1:1. Watson's theory of care nursing was applied in the observation group, and VAP eye gel was additionally dropped into the eye. Mouse conjunctival goblet cells (GCs) were used to detect the effect of VAP on the growth of GCs. Treatment compliance, improvement of dry eye symptoms [Schirmer I test (SIT), tear film break-up time (BUT), and fluorescent staining (FL) score], inflammatory factor levels in tears, clinical efficacy, and parents' satisfaction were compared. RESULTS: It was found that VAP eye gel could better promote the proliferation of GCs. After nursing and clinical treatment, the dry eye symptoms were improved in all included children, and improvements in the SIT, BUT, and FL scores were more obvious in the observation group. Watson's theory of care nursing could effectively improve the children's treatment compliance and parents' satisfaction. CONCLUSIONS: As a result, the application of VAP eye gel and Watson's theory of care nursing could effectively reduce the occurrence of dry eye after strabismus surgery, and were of great importance for improving the relationship between nurses and patients and building a harmonious hospital. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100049136.

12.
Org Lett ; 22(22): 8758-8763, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33151082

ABSTRACT

A meta-dehydrogenative alkylation of arenes with cyclic ethers, ketones, and esters catalyzed by ruthenium is achieved in the presence of a di-tert-butyl peroxide (DTBP) oxidant. Interestingly, when quinoline and isoquinoline are employed as the directing group, or a chain ether as alkylation reagent, the system produces Minisci reaction products. Mechanistic study indicates that meta-dehydrogenative alkylation is a radical process initiated by DTBP with the assistance of a CAr-Ru bond ortho/para-directing effect.

13.
Org Lett ; 22(24): 9450-9455, 2020 Dec 18.
Article in English | MEDLINE | ID: mdl-33232169

ABSTRACT

m-CAr-H bond functionalization of tertiary phosphines was developed using [Ru(p-cymene)Cl2]2 as a catalyst. Desired product structures were confirmed by single-crystal X-ray diffraction. Mechanistic experiments indicated that m-CAr-H bond functionalization was a radical reaction and that a hexagonal ruthenacycle complex was a crucial intermediate in the process. Therefore, this study provides a novel method for the late-stage meta-position modification of biphenyl monophosphine ligands.

14.
RSC Adv ; 10(31): 18526-18532, 2020 May 10.
Article in English | MEDLINE | ID: mdl-35517237

ABSTRACT

A highly sensitive and selective electrochemical sensor modified with poly-(l-cysteine)/CuO nanoneedles/N-doped reduced graphene oxide (l-Cys/NN-CuO/N-rGO) has been prepared for the testing of trace Pb2+. The electrochemical performance of this proposed sensor was investigated using electrochemical impedance spectroscopy (EIS). Based on the excellent electrochemical properties of NN-CuO/N-rGO as well as the specific complexation of natural substance l-cysteine with Pb2+, the l-Cys/NN-CuO/N-rGO was applied as a voltammetric biosensor for the determination of trace Pb2+ at pH 5.0. Under the optimum experimental conditions, the voltammetric peak current was linear with the Pb2+ concentration over the range from 0.001 to 5.0 nM and 5.0 to 1000 nM, respectively, with a low detection limit for Pb2+ concentration on the biosensor of 8.0 × 10-5 nM (S/N = 3). The significant sensitivity, selectivity, and electron conductivity of this l-Cys/NN-CuO/N-rGO modified electrode have also been studied. The specific detection of Pb2+ in water samples was also carried out.

15.
RSC Adv ; 9(27): 15217-15223, 2019 May 14.
Article in English | MEDLINE | ID: mdl-35514807

ABSTRACT

A zeolitic imidazolate framework-8 (ZIF-8)/reduced graphene oxide (rGO) nanocomposite was formed by using an efficient synthetic method. The morphology and structure of the ZIF-8/rGO nanocomposite were characterized by scanning electron spectroscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) mapping. The ZIF-8/rGO nanocomposites were immobilized on a carbon paste electrode (CPE) to construct a high-performance nonenzymatic electrochemical H2O2 sensor. A cyclic voltammetry (CV) study showed that the ZIF-8/rGO nanocomposites displayed better electrocatalytic activity toward H2O2 reduction compared to that of ZIF-8. An amperometric study indicated that the H2O2 sensor displayed high performance, which offered a low detection limit (0.05 µM) (S/N = 3), a high sensitivity (4.01 µA mM-1 cm-2), and a wide linear range (from 1.0 to 625 µM). An electrochemical reaction mechanism was proposed for H2O2 reduction on the ZIF-8/rGO/CPE. Importantly, the as-fabricated H2O2 sensor exhibited good reproducibility and excellent selectivity. Furthermore, the constructed high-performance sensor was utilized to monitor the H2O2 levels in real samples, and satisfactory results were obtained. These results demonstrated that the ZIF-8/rGO nanocomposite can be used as a good electrochemical sensor material in practical applications.

16.
Org Lett ; 19(19): 5166-5169, 2017 10 06.
Article in English | MEDLINE | ID: mdl-28915049

ABSTRACT

The first example of transition-metal-catalyzed ortho/meta-selective dual C-H functionalizations of arenes in one reaction is described. In this transformation, ortho-C-H chlorination and meta-C-H sulfonation of 2-phenoxypyri(mi)dines were achieved simultaneously under catalysis by [Ru(p-cymene)Cl2]2. The other reactant, namely, an arylsulfonyl chloride, played the role of both a sulfonation and chlorination reagent. More importantly, the arylsulfonyl chloride was also an oxidant in the process. Mechanistic studies indicated that six-membered ruthenacycles were the key intermediate in the reaction.

17.
Org Lett ; 19(10): 2682-2685, 2017 05 19.
Article in English | MEDLINE | ID: mdl-28481100

ABSTRACT

The first example of the synthesis of m-alkylphenols via a ruthenium-catalyzed CAr-H bond functionalization of phenol derivatives with sec/tert-alkyl bromides is reported. Mechanistic studies indicated that the m-CAr-H bond alkylation may involve a radical process and that a six-membered ruthenacycle complex was the active catalyst. Moreover, this approach can provide an expedited strategy for the atom-/step-economical synthesis of many noteworthy pharmaceuticals and other functional molecules.

18.
Chem Commun (Camb) ; 53(7): 1261-1264, 2017 Jan 19.
Article in English | MEDLINE | ID: mdl-28067355

ABSTRACT

meta/ortho-Selective CAr-H (di)alkylation reactions of azoarenes have been achieved via [Ru(p-cymene)Cl2]2 catalyzed ortho-metalation using various types of alkyl bromides. Particularly, dual meta-alkylation of azoarene and reduction offer an attractive strategy for the synthesis of meta-alkylanilines, which are difficult to access via traditional aniline functionalization methods.

19.
Org Biomol Chem ; 13(46): 11184-8, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26478119

ABSTRACT

Metal-free methylation of a pyridine N-oxide C-H bond was developed using peroxide as a methyl reagent under neat conditions. Pyridine N-oxide derivatives with various groups (e.g., Cl, NO2, and OCH3) were all suitable substrates, and the desired products were obtained in moderate to excellent yields under standard conditions. Moreover, the methylation can be performed with a good yield on the gram-scale experiment. Tentative mechanistic studies show that the methylation is a classical radical process.

20.
Bioresour Technol ; 172: 180-185, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25261865

ABSTRACT

Mixotrophic cultivation is one potential mode for microalgae production, and an economically acceptable and environmentally sustainable organic carbon source is essential. The potential use of xylose for culturing Scenedesmus obliquus in a mixotrophic mode and physiological features of xylose-grown S. obliquus were studied. S. obliquus had a certain xylose tolerance, and was capable of utilizing xylose for growth. At a xylose concentration of 4gL(-1), the maximal cell density was 2.2gL(-1), being 2.9-fold of that under photoautotrophic condition and arriving to the level of mixotrophic growth using 4gL(-1) glucose. No changes in cellular morphology of the cells grown with or without xylose were detected. Fluorescence emission from photosystem II (PS II) relative to photosystem I (PS I) was decreased in mixotrophic cells, implying that the PSII activity was decreased. The biomass lipid content was enhanced and carbohydrate concentration was decreased, in relation to photoautotrophic controls.


Subject(s)
Biomass , Scenedesmus/physiology , Xylose/metabolism , Aldehyde Reductase/metabolism , Fluorescence , Pigments, Biological/analysis , Scenedesmus/chemistry , Scenedesmus/cytology
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