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1.
Front Immunol ; 15: 1360700, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736886

RESUMO

Introduction: Myocardial infarction (MI) is a significant contributor to morbidity and mortality worldwide. Many individuals who survive the acute event continue to experience heart failure (HF), with inflammatory and healing processes post-MI playing a pivotal role. Polymorphonuclear neutrophils (PMN) and monocytes infiltrate the infarcted area, where PMN release high amounts of the heme enzyme myeloperoxidase (MPO). MPO has numerous inflammatory properties and MPO plasma levels are correlated with prognosis and severity of MI. While studies have focused on MPO inhibition and controlling PMN infiltration into the infarcted tissue, less is known on MPO's role in monocyte function. Methods and results: Here, we combined human data with mouse and cell studies to examine the role of MPO on monocyte activation and migration. We revealed a correlation between plasma MPO levels and monocyte activation in a patient study. Using a mouse model of MI, we demonstrated that MPO deficiency led to an increase in splenic monocytes and a decrease in cardiac monocytes compared to wildtype mice (WT). In vitro studies further showed that MPO induces monocyte migration, with upregulation of the chemokine receptor CCR2 and upregulation of inflammatory pathways identified as underlying mechanisms. Conclusion: Taken together, we identify MPO as a pro-inflammatory mediator of splenic monocyte recruitment and activation post-MI and provide mechanistic insight for novel therapeutic strategies after ischemic injury.


Assuntos
Monócitos , Infarto do Miocárdio , Peroxidase , Animais , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Peroxidase/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Humanos , Camundongos , Masculino , Movimento Celular , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Feminino , Neutrófilos/imunologia , Neutrófilos/metabolismo , Camundongos Knockout , Receptores CCR2/metabolismo , Pessoa de Meia-Idade
2.
BMC Genom Data ; 25(1): 41, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711007

RESUMO

BACKGROUND: Class III peroxidase (POD) enzymes play vital roles in plant development, hormone signaling, and stress responses. Despite extensive research on POD families in various plant species, the knowledge regarding the POD family in Chinese pear (Pyrus bretschenedri) is notably limited. RESULTS: We systematically characterized 113 POD family genes, designated as PbPOD1 to PbPOD113 based on their chromosomal locations. Phylogenetic analysis categorized these genes into seven distinct subfamilies (I to VII). The segmental duplication events were identified as a prevalent mechanism driving the expansion of the POD gene family. Microsynteny analysis, involving comparisons with Pyrus bretschenedri, Fragaria vesca, Prunus avium, Prunus mume and Prunus persica, highlighted the conservation of duplicated POD regions and their persistence through purifying selection during the evolutionary process. The expression patterns of PbPOD genes were performed across various plant organs and diverse fruit development stages using transcriptomic data. Furthermore, we identified stress-related cis-acting elements within the promoters of PbPOD genes, underscoring their involvement in hormonal and environmental stress responses. Notably, qRT-PCR analyses revealed distinctive expression patterns of PbPOD genes in response to melatonin (MEL), salicylic acid (SA), abscisic acid (ABA), and methyl jasmonate (MeJA), reflecting their responsiveness to abiotic stress and their role in fruit growth and development. CONCLUSIONS: In this study, we investigated the potential functions and evolutionary dynamics of PbPOD genes in Pyrus bretschenedri, positioning them as promising candidates for further research and valuable indicators for enhancing fruit quality through molecular breeding strategies.


Assuntos
Regulação da Expressão Gênica de Plantas , Filogenia , Reguladores de Crescimento de Plantas , Pyrus , Pyrus/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Melatonina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oxilipinas/farmacologia , Ciclopentanos/farmacologia , Peroxidase/genética , Peroxidase/metabolismo , Acetatos/farmacologia , Acetatos/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento
3.
ACS Nano ; 18(19): 12367-12376, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38695521

RESUMO

Bimetallic nanoparticles (NPs) with peroxidase-like (POD-like) activity play a crucial role in biosensing, disease treatment, environmental management, and other fields. However, their development is impeded by a vast range of tunable properties in components and structures, making the establishment of structure-effect relationships and the discovery of active materials challenging. Addressing this, we established robust scaling relationships by meticulously analyzing the catalytic reaction networks of pure metal NPs, which laid the volcano-shaped correlation between the activity and O* adsorption energy. Utilizing these relationships, we introduced an innovative and versatile descriptor of the NPs, which was then integrated into a machine learning-accelerated high-throughput computational workflow, significantly boosting the predictive accuracy for the POD-like activity of bimetallic NPs. Our methodological approach enabled the successful prediction of activities for 1260 bimetallic NPs, leading to the identification of several highly effective catalysts. Furthermore, we distilled several strategies for designing efficient bimetallic NPs based on our screening results.


Assuntos
Aprendizado de Máquina , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Catálise , Peroxidase/química , Peroxidase/metabolismo , Ensaios de Triagem em Larga Escala/métodos
4.
J Immunol Res ; 2024: 4283928, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699219

RESUMO

Objective: To characterize the eosinophilic granulomatosis with polyangiitis (EGPA) population from the POLVAS registry depending on ANCA status and diagnosis onset, including their comparison with the granulomatosis with polyangiitis (GPA) subset with elevated blood eosinophilia (min. 400/µl) (GPA HE) to develop a differentiating strategy. Methods: A retrospective analysis of the POLVAS registry. Results: The EGPA group comprised 111 patients. The ANCA-positive subset (n = 45 [40.54%]) did not differ from the ANCA-negative one in clinics. Nevertheless, cardiovascular manifestations were more common in ANCA-negative patients than in those with anti-myeloperoxidase (MPO) antibodies (46.97% vs. 26.92%, p = 0.045). Patients diagnosed before 2012 (n = 70 [63.06%]) were younger (median 41 vs. 49 years, p < 0.01), had higher blood eosinophilia at diagnosis (median 4,946 vs. 3,200/µl, p < 0.01), and more often ear/nose/throat (ENT) and cardiovascular involvement. GPA HE comprised 42 (13.00%) out of 323 GPA cases with reported blood eosinophil count. Both GPA subsets had a lower prevalence of respiratory, cardiovascular, and neurologic manifestations but more often renal and ocular involvement than EGPA. EGPA also had cutaneous and gastrointestinal signs more often than GPA with normal blood eosinophilia (GPA NE) but not GPA HE. The model differentiating EGPA from GPA HE, using ANCA status and clinical manifestations, had an AUC of 0.92, sensitivity of 96%, and specificity of 95%. Conclusion: Cardiovascular symptoms were more prevalent in the ANCA-negative subset than in the MPO-ANCA-positive one. Since EGPA and GPE HE share similarities in clinics, diagnostic misleading may result in an inappropriate therapeutic approach. Further studies are needed to optimize their differentiation and tailored therapy, including biologics.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos , Eosinofilia , Sistema de Registros , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Estudos Retrospectivos , Eosinofilia/diagnóstico , Eosinofilia/imunologia , Eosinofilia/sangue , Anticorpos Anticitoplasma de Neutrófilos/sangue , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Granulomatose com Poliangiite/diagnóstico , Granulomatose com Poliangiite/imunologia , Idoso , Síndrome de Churg-Strauss/diagnóstico , Síndrome de Churg-Strauss/imunologia , Síndrome de Churg-Strauss/epidemiologia , Peroxidase/imunologia , Eosinófilos/imunologia
5.
PLoS One ; 19(5): e0301358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38771804

RESUMO

Drug-resistant bacteria arising from antibiotic abuse infections have always been a serious threat to human health. Killing bacteria with toxic reactive oxygen species (ROS) is an ideal antibacterial method for treating drug-resistant bacterial infections. Here, we prepared Pt-Ru bimetallic nanoclusters (Pt-Ru NCs) with higher peroxidase (POD)-like activity than Pt monometallic nanoclusters. Pt-Ru can easily catalyze the decomposition of H2O2 to produce ·OH, thereby catalyzing the transformation of 3,3',5,5'-tetramethylbiphenylamine (TMB) to blue oxidized TMB (oxTMB). We utilized the POD-like activity of the Pt-Ru NCs for antibacterial therapy. The results showed that at doses of 40 µg/mL and 16 µg/mL, the Pt-Ru NCs exhibited extraordinary antibacterial activity against E. coli and S. aureus, demonstrating the enormous potential of Pt-Ru NCs as antibacterial agents.


Assuntos
Antibacterianos , Escherichia coli , Nanopartículas Metálicas , Platina , Rutênio , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Platina/química , Platina/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Rutênio/química , Rutênio/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Peroxidase/metabolismo , Peróxido de Hidrogênio/química , Catálise , Humanos
6.
Anal Chim Acta ; 1309: 342698, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38772661

RESUMO

BACKGROUND: The lateral flow immunoassay (LFIA) is widely employed as a point-of-care testing (POCT) technique. However, its limited sensitivity hinders its application in detecting biomarkers with low abundance. Recently, the utilization of nanozymes has been implemented to enhance the sensitivity of LFIA by catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). The catalytic performance of nanozymes plays a crucial role in influencing the sensitivity of LFIA. RESULTS: The Cornus officinalis Sieb. et Zucc-Pd@Pt (CO-Pd@Pt) nanozyme with good peroxidase-like activity was synthesized herein through a facile one-pot method employing Cornus officinalis Sieb. et Zucc extract as a reducing agent. The morphology and composition of the CO-Pd@Pt nanozyme were characterized using TEM, SEM, XRD, and XPS. As a proof of concept, the as-synthesized CO-Pd@Pt nanozyme was utilized in LFIA (CO-Pd@Pt-LFIA) for the detection of human chorionic gonadotropin (hCG). Compared to conventional gold nanoparticles-based LFIA (AuNPs-LFIA), CO-Pd@Pt-LFIA demonstrated a significant enhancement in the limit of detection (LOD, 0.08 mIU/mL), which is approximately 160 times lower than that of AuNPs-LFIA. Furthermore, experiments evaluating accuracy, precision, selectivity, interference, and stability have confirmed the practical applicability of CO-Pd@Pt-LFIA for hCG content determination. SIGNIFICANCE: The present study presents a novel approach for the synthesis of bimetallic nanozymes through environmentally friendly methods, utilizing plant extracts as both protective and reducing agents. Additionally, an easily implementable technique is proposed to enhance signal detection in lateral flow immunoassays.


Assuntos
Paládio , Platina , Paládio/química , Platina/química , Imunoensaio/métodos , Humanos , Nanopartículas Metálicas/química , Limite de Detecção , Peroxidase/química , Peroxidase/metabolismo , Benzidinas/química , Catálise , Oxirredução
7.
Arch Biochem Biophys ; 756: 110023, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705227

RESUMO

Myeloperoxidase is a critical component of the antibacterial arsenal of neutrophils, whereby it consumes H2O2 as an oxidant to convert halogen and pseudohalogen anions into cytotoxic hypohalous acids. Following phagocytosis by neutrophils, the human pathogen Staphylococcus aureus secretes a potent myeloperoxidase inhibitory protein, called SPIN, as part of its immune evasion repertoire. The matured S. aureus SPIN polypeptide consists of only 73 residues yet contains two functional domains: whereas the 60 residue C-terminal helical bundle domain is responsible for MPO binding, the 13 residue N-terminal domain is required to inhibit MPO. Previous studies have informed understanding of the SPIN N-terminal domain, but comparatively little is known about the helical domain insofar as the contribution of individual residues is concerned. To address this limitation, we carried out a residue-level structure/function investigation on the helical bundle domain of S. aureus SPIN. Using sequence conservation and existing structures of SPIN bound to human MPO as a guide, we selected residues L49, E50, H51, E52, Y55, and Y75 for interrogation by site-directed mutagenesis. We found that loss of L49 or E52 reduced SPIN activity by roughly an order of magnitude, but that loss of Y55 or H51 caused progressively greater loss of inhibitory potency. Direct binding studies by SPR showed that loss of inhibitory potency in these SPIN mutants resulted from a diminished initial interaction between the inhibitor and MPO. Together, our studies provide new insights into the structure/function relationships of SPIN and identify positions Y55 and H51 as critical determinants of SPIN function.


Assuntos
Peroxidase , Staphylococcus aureus , Staphylococcus aureus/enzimologia , Humanos , Peroxidase/química , Peroxidase/metabolismo , Peroxidase/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Domínios Proteicos , Sequência de Aminoácidos , Mutagênese Sítio-Dirigida , Modelos Moleculares , Conformação Proteica em alfa-Hélice
8.
Bull Exp Biol Med ; 176(5): 607-611, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38730105

RESUMO

The study presents the killer functions of circulating neutrophils: myeloperoxidase activity, the ability to generate ROS, phagocytic activity, receptor status, NETosis, as well as the level of cytokines IL-2, IL-4, IL-6, IL-17A, and IL-18, granulocyte CSF, monocyte chemotactic protein 1, and neutrophil elastase in the serum of patients with uterine myoma and endometrial cancer (FIGO stages I-III). The phagocytic ability of neutrophils in uterine myoma was influenced by serum levels of granulocyte CSF and IL-2 in 54% of the total variance. The degranulation ability of neutrophils in endometrial cancer was determined by circulating IL-18 in 50% of the total variance. In uterine myoma, 66% of the total variance in neutrophil myeloperoxidase activity was explained by a model dependent on blood levels of IL-17A, IL-6, and IL-4. The risk of endometrial cancer increases when elevated levels of monocyte chemotactic protein 1 in circulating neutrophils are associated with reduced ability to capture particles via extracellular traps (96% probability).


Assuntos
Quimiocina CCL2 , Neoplasias do Endométrio , Interleucina-17 , Interleucina-6 , Neutrófilos , Humanos , Feminino , Neutrófilos/metabolismo , Neutrófilos/imunologia , Neoplasias do Endométrio/imunologia , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/metabolismo , Interleucina-6/sangue , Quimiocina CCL2/sangue , Interleucina-17/sangue , Pessoa de Meia-Idade , Interleucina-4/sangue , Peroxidase/sangue , Peroxidase/metabolismo , Interleucina-18/sangue , Neoplasias Uterinas/sangue , Neoplasias Uterinas/imunologia , Neoplasias Uterinas/patologia , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos/metabolismo , Fagocitose , Leiomioma/sangue , Leiomioma/imunologia , Leiomioma/patologia , Leiomioma/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Elastase de Leucócito/sangue , Elastase de Leucócito/metabolismo , Adulto , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/imunologia , Espécies Reativas de Oxigênio/metabolismo , Idoso , Interleucina-2
9.
Biosens Bioelectron ; 258: 116351, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705074

RESUMO

Multifunctional single-atom catalysts (SACs) have been extensively investigated as outstanding signal amplifiers in bioanalysis field. Herein, a type of Fe single-atom catalysts with Fe-nitrogen coordination sites in nitrogen-doped carbon (Fe-N/C SACs) was synthesized and demonstrated to possess both catalase and peroxidase-like activity. Utilizing Fe-N/C SACs as dual signal amplifier, an efficient bipolar electrode (BPE)-based electrochemiluminescence (ECL) immunoassay was presented for determination of prostate-specific antigen (PSA). The cathode pole of the BPE-ECL platform modified with Fe-N/C SACs is served as the sensing side and luminol at the anode as signal output side. Fe-N/C SACs could catalyze decomposition of H2O2 via their high catalase-like activity and then increase the Faraday current, which can boost the ECL of luminol due to the electroneutrality in a closed BPE system. Meanwhile, in the presence of the target, glucose oxidase (GOx)-Au NPs-Ab2 was introduced through specific immunoreaction, which catalyzes the formation of H2O2. Subsequently, Fe-N/C SACs with peroxidase-like activity catalyze the reaction of H2O2 and 4-chloro-1-naphthol (4-CN) to generate insoluble precipitates, which hinders electron transfer and then inhibits the ECL at the anode. Thus, dual signal amplification of Fe-N/C SACs was achieved by increasing the initial ECL and inhibiting the ECL in the presence of target. The assay exhibits sensitive detection of PSA linearly from 1.0 pg/mL to 100 ng/mL with a detection limit of 0.62 pg/mL. The work demonstrated a new ECL enhancement strategy of SACs via BPE system and expands the application of SACs in bioanalysis field.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Peróxido de Hidrogênio , Ferro , Limite de Detecção , Medições Luminescentes , Luminol , Antígeno Prostático Específico , Catálise , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Humanos , Luminol/química , Antígeno Prostático Específico/análise , Antígeno Prostático Específico/sangue , Ferro/química , Glucose Oxidase/química , Imunoensaio/métodos , Ouro/química , Peroxidase/química , Nanopartículas Metálicas/química , Nitrogênio/química , Carbono/química , Naftóis
10.
Biosens Bioelectron ; 258: 116370, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744115

RESUMO

Protein phosphorylation is a significant post-translational modification that plays a decisive role in the occurrence and development of diseases. However, the rapid and accurate identification of phosphoproteins remains challenging. Herein, a high-throughput sensor array has been constructed based on a magnetic bimetallic nanozyme (Fe3O4@ZNP@UiO-66) for the identification and discrimination of phosphoproteins. Attributing to the formation of Fe-Zr bimetallic dual active centers, the as-prepared Fe3O4@ZNP@UiO-66 exhibits enhanced peroxidase-mimicking catalytic activity, which promotes the electron transfer from Zr center to Fe(II)/Fe(III). The catalytic activity of Fe3O4@ZNP@UiO-66 can be selectively inhibited by phosphoproteins due to the strong interaction between phosphate groups and Zr centers, as well as the ultra-robust antifouling capability of zwitterionic dopamine nanoparticle (ZNP). Considering the diverse binding affinities between various proteins with the nanozyme, the catalytic activity of Fe3O4@ZNP@UiO-66 can be changed to various degree, leading to the different absorption responses at 420 nm in the hydrogen peroxide (H2O2) - 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) system. By simply extracting different absorbance intensities at various time points, a sensor array based on reaction kinetics for the discrimination of phosphoproteins from other proteins is constructed through linear discriminant analysis (LDA). Besides, the quantitative determination of phosphoproteins and identification of protein mixtures have been realized. Further, based on the differential level of phosphoproteins in cells, the differentiation of cancer cells from normal cells can also be implemented by utilizing the proposed sensor array, showing great potential in disease diagnosis.


Assuntos
Técnicas Biossensoriais , Peróxido de Hidrogênio , Neoplasias , Fosfoproteínas , Zircônio , Técnicas Biossensoriais/métodos , Humanos , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Peróxido de Hidrogênio/química , Zircônio/química , Peroxidase/química , Dopamina/química , Limite de Detecção , Materiais Biomiméticos/química , Catálise
11.
Mikrochim Acta ; 191(6): 331, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744722

RESUMO

A broad host range phage-based nanozyme (Fe-MOF@SalmpYZU47) was prepared for colorimetric detection of multiple Salmonella enterica strains. The isolation of a broad host range phage (SalmpYZU47) capable of infecting multiple S. enterica strains was achieved. Then, it was directly immobilized onto the Fe-MOF to prepare Fe-MOF@SalmpYZU47, exhibiting peroxidase-like activity. The peroxidase-like activity can be specifically inhibited by multiple S. enterica strains, benefiting from the broad host range capture ability of Fe-MOF@SalmpYZU47. Based on it, a colorimetric detection approach was developed for S. enterica in the range from 1.0 × 102 to 1.0 × 108 CFU mL-1, achieving a low limit of detection (LOD) of 11 CFU mL-1. The Fe-MOF@SalmpYZU47 was utilized for detecting S. enterica in authentic food samples, achieving recoveries ranging from 91.88 to 105.34%. Hence, our proposed broad host range phage-based nanozyme exhibits significant potential for application in the colorimetric detection of pathogenic bacteria.


Assuntos
Colorimetria , Limite de Detecção , Estruturas Metalorgânicas , Salmonella enterica , Colorimetria/métodos , Salmonella enterica/isolamento & purificação , Salmonella enterica/química , Estruturas Metalorgânicas/química , Microbiologia de Alimentos/métodos , Contaminação de Alimentos/análise , Peroxidase/química
12.
J Am Chem Soc ; 146(15): 10478-10488, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578196

RESUMO

During biomedical applications, nanozymes, exhibiting enzyme-like characteristics, inevitably come into contact with biological fluids in living systems, leading to the formation of a protein corona on their surface. Although it is acknowledged that molecular adsorption can influence the catalytic activity of nanozymes, there is a dearth of understanding regarding the impact of the protein corona on nanozyme activity and its determinant factors. In order to address this gap, we employed the AuNR@Pt@PDDAC [PDDAC, poly(diallyldimethylammonium chloride)] nanorod (NR) as a model nanozyme with multiple activities, including peroxidase, oxidase, and catalase-mimetic activities, to investigate the inhibitory effects of the protein corona on the catalytic activity. After the identification of major components in the plasma protein corona on the NR, we observed that spherical proteins and fibrous proteins induced distinct inhibitory effects on the catalytic activity of nanozymes. To elucidate the underlying mechanism, we uncovered that the adsorbed proteins assembled on the surface of the nanozymes, forming protein networks (PNs). Notably, the PNs derived from fibrous proteins exhibited a screen mesh-like structure with smaller pore sizes compared to those formed by spherical proteins. This structural disparity resulted in a reduced efficiency for the permeation of substrate molecules, leading to a more robust inhibition in activity. These findings underscore the significance of the protein shape as a crucial factor influencing nanozyme activity. This revelation provides valuable insights for the rational design and application of nanozymes in the biomedical fields.


Assuntos
Nanoestruturas , Coroa de Proteína , Escleroproteínas , Peroxidase , Adsorção , Corantes , Catálise
13.
Physiol Plant ; 176(2): e14294, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38634335

RESUMO

In our comprehensive meta-analysis, we initially collected 177 publications focusing on the impact of melatonin on wheat. After meticulous screening, 40 published studies were selected, encompassing 558 observations for antioxidant enzymes, 312 for reactive oxygen species (ROS), and 92 for soluble biomolecules (soluble sugar and protein). This analysis revealed significant heterogeneity across studies (I2 > 99% for enzymes, ROS, and soluble biomolecules) and notable publication bias, indicating the complexity and variability in the research field. Melatonin application generally increased antioxidant enzyme activities [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)] in wheat, particularly under stress conditions, such as high temperature and heavy-metal exposure. Compared to control, melatonin application increased SOD, POD, CAT, and APX activities by 29.5, 16.96, 35.98, and 171.64%, respectively. Moreover, oxidative stress markers like hydrogen peroxide (H2O2), superoxide anion (O2), and malondialdehyde (MDA) decreased with melatonin by 23.73, 13.64, and 21.91%, respectively, suggesting a reduction in oxidative stress. The analysis also highlighted melatonin's role in improving carbohydrate metabolism and antioxidant defenses. Melatonin showed an overall increase of 12.77% in soluble sugar content, and 22.76% in glutathione peroxidase (GPX) activity compared to the control. However, the effects varied across different wheat varieties, environmental conditions, and application methods. Our study also uncovered complex relationships between antioxidant enzyme activities and H2O2 levels, indicating a nuanced regulatory role of melatonin in oxidative stress responses. Our meta-analysis demonstrates the significant role of melatonin in increasing wheat resilience to abiotic stressors, potentially through its regulatory impact on antioxidant defense systems and stress response.


Assuntos
Antioxidantes , Melatonina , Antioxidantes/metabolismo , Melatonina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Triticum/metabolismo , Peróxido de Hidrogênio/metabolismo , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Peroxidases/metabolismo , Peroxidase/metabolismo , Estresse Oxidativo , Açúcares/metabolismo , Malondialdeído/metabolismo
14.
Biosens Bioelectron ; 255: 116259, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574559

RESUMO

Carbon-based nanozymes possessing peroxidase-like activity have attracted significant interest because of their potential to replace native peroxidases in biotechnology. Although various carbon-based nanozymes have been developed, their relatively low catalytic efficiency needs to be overcome to realize their practical utilization. Here, inspired by the elemental uniqueness of Cu and the doped elements N and S, as well as the active site structure of Cu-centered oxidoreductases, we developed a new carbon-based peroxidase-mimicking nanozyme, single-atom Cu-centered N- and S-codoped reduced graphene oxide (Cu-NS-rGO), which preserved many Cu-N4 and Cu-N4S active sites and showed dramatically high peroxidase-like activity without any oxidase-like activity, yielding up to 2500-fold higher catalytic efficiency (kcat/Km) than that of pristine rGO. The high catalytic activity of Cu-NS-rGO might be attributed to the acceleration of electron transfer from Cu single atom as well as synergistic effects from both Cu-N4 and Cu-N4S active sites, which was theoretically confirmed by Gibbs free energy calculations using density functional theory. The prepared Cu-NS-rGO was then used to construct an electrochemical bioassay system for detecting choline and acetylcholine by coupling with the corresponding oxidases. Using this system, both target molecules were selectively determined with high sensitivity that was sufficient to clinically determine their levels in physiological fluids. Overall, this study will facilitate the development of nanocarbon-based nanozymes and their electrochemical biosensing applications, which can be extended to the development of miniaturized devices in point-of-care testing environments.


Assuntos
Técnicas Biossensoriais , Grafite , Peroxidase , Peroxidase/química , Domínio Catalítico , Peroxidases/química , Oxirredutases , Carbono/química
15.
Biosens Bioelectron ; 255: 116271, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583355

RESUMO

The metal-organic frameworks (MOFs) nanozyme-mediated paper-based analytical devices (PADs) have shown great potential in portable visual determination of phenolic compounds in the environment. However, most MOF nanozymes suffer from poor dispersibility and block-like structure, which often prompts deposition and results in diminished enzymatic activity, severely hindering their environmental applications. Here, we proposed colorimetric PADs for the visual detection of dichlorophen (Dcp) based on its significant inhibitory effect on the two-dimensional (2D) MOF nanozyme activity. Specifically, we synthesized a 2D Cu TCPP (Fe) (defined as 2D-CTF) MOF nanozyme exhibiting excellent dispersibility and remarkable peroxidase-like (POD-like) activity, which could catalyze the oxidation and subsequent color change of 3,3',5,5'-tetramethylbenzidine even under neutral conditions. Notably, the POD-like activity of 2D-CTF demonstrated a unique response to Dcp because of the occupation of Fe-N4 active sites on the 2D-CTF. This property enables the use of 2D-CTF as a highly efficient catalyst to develop colorimetric PADs for naked-eye and portable detection of Dcp. We believe that the proposed colorimetric PADs offer an efficient method for Dcp assay and open fresh avenues for the advancement of colorimetric sensors for analyzing of phenolic toxic substances in real samples.


Assuntos
Técnicas Biossensoriais , Diclorofeno , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Técnicas Biossensoriais/métodos , Peroxidases/química , Peroxidase , Colorimetria/métodos , Fenóis , Peróxido de Hidrogênio/química
16.
Anal Chem ; 96(15): 6072-6078, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38577757

RESUMO

The urgent need for sensitive and accurate assays to monitor acetylcholinesterase (AChE) activity and organophosphorus pesticides (OPs) arises from the imperative to safeguard human health and protect the ecosystem. Due to its cost-effectiveness, ease of operation, and rapid response, nanozyme-based colorimetry has been widely utilized in the determination of AChE activity and OPs. However, the rational design of nanozymes with high activity and specificity remains a great challenge. Herein, trace amount of Bi-doped core-shell Pd@Pt mesoporous nanospheres (Pd@PtBi2) have been successfully synthesized, exhibiting good peroxidase-like activity and specificity. With the incorporation of trace bismuth, there is a more than 4-fold enhancement in the peroxidase-like performance of Pd@PtBi2 compared to that of Pd@Pt. Besides, no significant improvement of oxidase-like and catalase-like activities of Pd@PtBi2 was found, which prevents interference from O2 and undesirable consumption of substrate H2O2. Based on the blocking impact of thiocholine, a colorimetric detection platform utilizing Pd@PtBi2 was constructed to monitor AChE activity with sensitivity and selectivity. Given the inhibition of OPs on AChE activity, a biosensor was further developed by integrating Pd@PtBi2 with AChE to detect OPs, capitalizing on the cascade amplification strategy. The OP biosensor achieved a detection limit as low as 0.06 ng mL-1, exhibiting high sensitivity and anti-interference ability. This work is promising for the construction of nanozymes with high activity and specificity, as well as the development of nanozyme-based colorimetric biosensors.


Assuntos
Técnicas Biossensoriais , Nanosferas , Agentes Neurotóxicos , Praguicidas , Humanos , Acetilcolinesterase/metabolismo , Compostos Organofosforados , Praguicidas/análise , Peróxido de Hidrogênio , Ecossistema , Oxirredutases , Peroxidase , Colorimetria
17.
Artigo em Chinês | MEDLINE | ID: mdl-38563171

RESUMO

Objective:To evaluate the expression of eosinophil cationic protein and myeloperoxidase in nasal secretions in different types of rhinitis, and to explore their values in the differential diagnosis of different types of rhinitis. Methods:Six hundred and eighty-four subjects were selected, including 62 subjects in the acute rhinitis group, 378 subjects in the allergic rhinitis group, 94 subjects in the vasomotor rhinitis group, 70 subjects in the eosinophilic non-allergic rhinitis group, and 80 subjects in the control group. Nasal secretion samples were collected from the five groups, and the percentages of inflammatory cells were counted by Rachel's staining, and the expression of ECP/MPO was detected by colloidal gold assay. The correlation between the clinical diagnosis, the inflammatory cells in the nasal secretions and the expression of ECP/MPO was analyzed. Results:Nasal cytological smears showed that compared with the control group, the percentage of eosinophils in the AR and NARES groups were significantly higher (P<0.05), while the percentage of neutrophils was not different (P>0.05); the percentage of neutrophils was significantly higher in the acute rhinitis group compared with the control group (P<0.05), while the percentage of eosinophils was not statistically different (P>0.05); in vasomotor rhinitis group, the eosinophils and neutrophils were not statistically different compared with the control group(P> 0.05). The colloidal gold results showed that there were differences in the expression of ECP/MPO in different types of rhinitis, among which 49 cases (79.0%) in the acute rhinitis group expressed ECP+/MPO+; 267 cases (70.6%) in the AR group and 56 cases (75.7%) in the NARES group expressed ECP+/MPO-; 80 cases (85.1%) in the vasomotor rhinitis group and 69 cases (86.3%) in the control group expressed ECP-/MPO-. Conclusion:The differences in ECP and MPO expression between different types of rhinitis have certain reference value for the differential diagnosis of different types of rhinitis and the selection of treatment programs.


Assuntos
Rinite Vasomotora , Rinite , Humanos , Eosinófilos/metabolismo , Coloide de Ouro/metabolismo , Mucosa Nasal/metabolismo , Peroxidase/metabolismo , Rinite/diagnóstico , Rinite/metabolismo , Rinite Vasomotora/metabolismo
18.
Clin Exp Med ; 24(1): 66, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564029

RESUMO

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients with dual positivity for proteinase 3-ANCA (PR3-ANCA) and myeloperoxidase-ANCA (MPO-ANCA) are uncommon. We aimed to investigate these idiopathic double-positive AAV patients' clinical features, histological characteristics, and prognosis. We reviewed all the electronic medical records of patients diagnosed with AAV to obtain clinical data and renal histological information from January 2010 to December 2020 in a large center in China. Patients were assigned to the MPO-AAV group or PR3-AAV group or idiopathic double-positive AAV group by ANCA specificity. We explored features of idiopathic double-positive AAV. Of the 340 patients who fulfilled the study inclusion criteria, 159 (46.76%) were female, with a mean age of 58.41 years at the time of AAV diagnosis. Similar to MPO-AAV, idiopathic double-positive AAV patients were older and had more severe anemia, lower Birmingham Vasculitis Activity Score (BVAS) and C-reactive protein (CRP) levels, less ear, nose, and throat (ENT) involvement, higher initial serum creatinine and a lower estimated glomerular filtration rate (eGFR) when compared with PR3-AAV (P < 0.05). The proportion of normal glomeruli of idiopathic double-positive AAV was the lowest among the three groups (P < 0.05). The idiopathic double-positive AAV patients had the worst remission rate (58.8%) among the three groups (P < 0.05). The relapse rate of double-positive AAV (40.0%) was comparable with PR3-AAV (44.8%) (P > 0.05). Although there was a trend toward a higher relapse rate of idiopathic double-positive AAV (40.0%) compared with MPO-AAV (23.5%), this did not reach statistical significance (P > 0.05). The proportion of patients who progressed to ESRD was 47.1% and 44.4% in the idiopathic double-positive AAV group and MPO-AAV group respectively, without statistical significance. Long-term patient survival also varied among the three groups (P < 0.05). Idiopathic double-positive AAV is a rare clinical entity with hybrid features of MPO-AAV and PR3-AAV. MPO-AAV is the "dominant" phenotype in idiopathic double-positive AAV.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Anticorpos Anticitoplasma de Neutrófilos , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Mieloblastina , Prognóstico , Peroxidase , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Recidiva
19.
Anal Methods ; 16(16): 2606-2613, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38618990

RESUMO

2,6-Pyridinedicarboxylic acid (DPA) is a significant biomarker of anthrax, which is a deadly infectious disease for human beings. However, the development of a convenient anthrax detection method is still a challenge. Herein, we report a novel europium metal-organic framework (Eu-MOF) with an enhanced peroxidase-like activity and fluorescence property for DPA detection. The Eu-MOF was one-step synthesized using Eu3+ ions and 2-methylimidazole. In the presence of DPA, the intrinsic fluorescence of Eu3+ ions is sensitized, the fluorescence intensity linearly increases with an increase in DPA concentration, and the fluorescence color changes from blue to purple. Simultaneously, the peroxide-like activity of the Eu-MOF is enhanced by DPA, which can promote the oxidation of TMB to oxTMB. The absorbance values increase linearly with DPA concentrations, and the colorimetric images change from colorless to blue. The dual-mode detection of DPA has good sensitivity with a colorimetric detection limit of 0.67 µM and a fluorescent detection limit of 16.67 nM. Moreover, a simple detection method for DPA was developed using a smartphone with the RGB analysis system. A portable kit with standard color cards was developed using paper test strips. The proposed methods have good practicability for DPA detection in real samples. In conclusion, the developed Eu-MOF biosensor offers a valuable and general platform for anthrax diagnosis.


Assuntos
Colorimetria , Európio , Estruturas Metalorgânicas , Ácidos Picolínicos , Európio/química , Estruturas Metalorgânicas/química , Colorimetria/métodos , Ácidos Picolínicos/análise , Ácidos Picolínicos/química , Limite de Detecção , Humanos , Fluorescência , Antraz/diagnóstico , Smartphone , Espectrometria de Fluorescência/métodos , Peroxidase/química , Peroxidase/metabolismo
20.
BMC Pulm Med ; 24(1): 207, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671448

RESUMO

OBJECTIVE: The aim of this research was to examine how penehyclidine hydrochloride (PHC) impacts the occurrence of pyroptosis in lung tissue cells within a rat model of lung ischemia-reperfusion injury. METHODS: Twenty-four Sprague Dawley (SD) rats, weighing 250 g to 270 g, were randomly distributed into three distinct groups as outlined below: a sham operation group (S group), a control group (C group), and a test group (PHC group). Rats in the PHC group received a preliminary intravenous injection of PHC at a dose of 3 mg/kg. At the conclusion of the experiment, lung tissue and blood samples were collected and properly stored for subsequent analysis. The levels of malondialdehyde, superoxide dismutase, and myeloperoxidase in the lung tissue, as well as IL-18 and IL-1ß in the blood serum, were assessed using an Elisa kit. Pyroptosis-related proteins, including Caspase1 p20, GSDMD-N, and NLRP3, were detected through the western blot method. Additionally, the dry-to-wet ratio (D/W) of the lung tissue and the findings from the blood gas analysis were also documented. RESULTS: In contrast to the control group, the PHC group showed enhancements in oxygenation metrics, reductions in oxidative stress and inflammatory reactions, and a decrease in lung injury. Additionally, the PHC group exhibited lowered levels of pyroptosis-associated proteins, including the N-terminal segment of gasdermin D (GSDMD-N), caspase-1p20, and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3). CONCLUSION: Pre-administration of PHC has the potential to mitigate lung ischemia-reperfusion injuries by suppressing the pyroptosis of lung tissue cells, diminishing inflammatory reactions, and enhancing lung function. The primary mechanism behind anti-pyroptotic effect of PHC appears to involve the inhibition of oxidative stress.


Assuntos
Gasderminas , Pulmão , Piroptose , Quinuclidinas , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Animais , Piroptose/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Ratos , Quinuclidinas/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Masculino , Malondialdeído/metabolismo , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-18/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Superóxido Dismutase/metabolismo , Peroxidase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Caspase 1/metabolismo , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/metabolismo
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