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1.
Food Chem ; 456: 139955, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38852453

RESUMO

The nanozyme-linked aptamer-sorbent assay (NLASA) is a rapid way to screen and characterize aptamer binding to targets. In this paper, a MnO2@AuNPs@aptamer (Apt) based NLASA coupled with colorimetric-SERS dual-mode for Staphylococcus aureus (S. aureus) detection is presented. Cu,Fe-CDs were used as the reducing agent to synthesize MnO2 and gold nanoparticles (AuNPs). Then, they were fabricated to obtain MnO2@AuNPs with oxidase (OXD)-like and SERS activities. The S. aureus aptamer was conjugated to MnO2@AuNPs and enhanced the OXD-like activity, which realized the specific capture of S. aureus in food matrices. In addition, S. aureus improves the oxidation of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid (ABTS) but inhibits 3,3',5,5'-tetramethylbenzidine (TMB) to generate Raman-active oxTMB with MnO2@AuNPs@Apt. This sensor was used for detections of S. aureus in a concentration ranged from 101 to 107 CFU/mL with a detection limit of 0.926 CFU/mL (colorimetric) and 1.561 CFU/mL (SERS), and the recovery is 85%-105% in real samples.

2.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38892463

RESUMO

Zea mays (maize) is a staple food, feed, and industrial crop. Heat stress is one of the major stresses affecting maize production and is usually accompanied by other stresses, such as drought. Our previous study identified a heterotrimer complex, ZmNF-YA1-YB16-YC17, in maize. ZmNF-YA1 and ZmNF-YB16 were positive regulators of the drought stress response and were involved in maize root development. In this study, we investigated whether ZmNF-YA1 confers heat stress tolerance in maize. The nf-ya1 mutant and overexpression lines were used to test the role of ZmNF-YA1 in maize thermotolerance. The nf-ya1 mutant was more temperature-sensitive than the wild-type (WT), while the ZmNF-YA1 overexpression lines showed a thermotolerant phenotype. Higher malondialdehyde (MDA) content and reactive oxygen species (ROS) accumulation were observed in the mutant, followed by WT and overexpression lines after heat stress treatment, while an opposite trend was observed for chlorophyll content. RNA-seq was used to analyze transcriptome changes in nf-ya1 and its wild-type control W22 in response to heat stress. Based on their expression profiles, the heat stress response-related differentially expressed genes (DEGs) in nf-ya1 compared to WT were grouped into seven clusters via k-means clustering. Gene Ontology (GO) enrichment analysis of the DEGs in different clades was performed to elucidate the roles of ZmNF-YA1-mediated transcriptional regulation and their contribution to maize thermotolerance. The loss function of ZmNF-YA1 led to the failure induction of DEGs in GO terms of protein refolding, protein stabilization, and GO terms for various stress responses. Thus, the contribution of ZmNF-YA1 to protein stabilization, refolding, and regulation of abscisic acid (ABA), ROS, and heat/temperature signaling may be the major reason why ZmNF-YA1 overexpression enhanced heat tolerance, and the mutant showed a heat-sensitive phenotype.


Assuntos
Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico , Proteínas de Plantas , Termotolerância , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/fisiologia , Resposta ao Choque Térmico/genética , Termotolerância/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mutação , Fator de Ligação a CCAAT/metabolismo , Fator de Ligação a CCAAT/genética , Perfilação da Expressão Gênica , Transcriptoma , Plantas Geneticamente Modificadas
3.
ACS Appl Mater Interfaces ; 16(25): 32619-32632, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860867

RESUMO

Nanozyme-mediated antioxidative therapy is a promising star for treating a myriad of important diseases through eliminating excessive reactive oxygen species (ROS) such as O2·- and H2O2, a critical mechanism for inflammatory bowel disease (IBD). This work provides a high biocompatibility iodine-copper-zinc covalent doped carbon dots (Cu,Zn,I-CDs) with the catalase (CAT)-, superoxide dismutase (SOD)- and glutathione peroxidase (GPx)-like catalytic activities for treating ulcerative colitis (UC) by scavenging overproduced ROS. We found that I dopant aids in counteracting the positive charge at Cu,Zn dopants brought on by low pH, enabling Cu,Zn,I-CDs to process strong triple antioxidant nanozyme activities rather than Cu,Zn-CDs. Vitro experiments displayed that the Cu,Zn,I-CDs could scavenge the excessive ROS to protect cellular against oxidative stress and reduce the expression of proinflammatory cytokines, such as TNF-α, IL-1ß, and IL-6. In sodium dextran sulfate (DSS)-induced colitis mice models, Cu,Zn,I-CDs with excellent biocompatibility could effectively relieve the inflammation of the colon, containing the reduction of the colon length, the damaged epithelium, the infiltration of inflammatory cells, and upregulation of antioxidant genes. Therefore, the therapy of Cu,Zn,I-CD antioxidant nanozymes is an effective approach and provides a novel strategy for UC treatment.


Assuntos
Antioxidantes , Carbono , Colite , Cobre , Sulfato de Dextrana , Pontos Quânticos , Zinco , Animais , Camundongos , Cobre/química , Cobre/farmacologia , Carbono/química , Antioxidantes/química , Antioxidantes/farmacologia , Pontos Quânticos/química , Zinco/química , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Espécies Reativas de Oxigênio/metabolismo , Iodo/química , Iodo/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Humanos , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Camundongos Endogâmicos C57BL
4.
Talanta ; 277: 126265, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38805947

RESUMO

The pathogenic bacteria induced foodborne disease has been detrimental to public health worldwide. Herein, the peroxidase (POD)-like Fe3O4/MWCNTs@Mo-CDs (FMMC) nanozyme was applied for the detection of Escherichia coli (E. coli). The E. coli aptamer was conjugated with the surface of the FMMC, which effectively enhanced the POD-like activity attributing to the higher affinity to the substrate, and then specific capture of E. coli in food matrices, leading to the reduction of POD-like activity. Therefore, a robust and facile colorimetric aptasensor was developed for detecting E. coli with a wide linear range of 101-106 CFU/mL, low LOQ of 101 CFU/mL and LOD of 0.978 CFU/mL. The aptasensor demonstrated the satisfied selectivity for E. coli compared to the other strains. This method possessed the potential application for fast in situ screening of foodborne pathogens in food products.

5.
Clin Cancer Res ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767620

RESUMO

PURPOSE: STAT3 is a key transcription factor that mediates cancer progression through phosphorylation or gain-of-function mutations. STAT3 activation in myeloid neoplasms (MNs) is primarily mediated through phosphorylation. STAT3 mutation has only rarely been reported in MNs. EXPERIMENTAL DESIGN: We assessed the clinicopathologic and molecular genetic features of 32 STAT3-mutated MNs. RESULTS: The frequency of STAT3 mutation in MNs was <0.5%. Twenty (62.5%) cases were classified as acute myeloid leukemia (AML), 7 (21.9%) as myelodysplastic syndrome (MDS), 5 (15.6%) as chronic myelomonocytic leukemia (CMML), but none as myeloproliferative neoplasms (MPN). STAT3 mutations occurred at initial diagnosis in 22 (88%) cases, or at relapse or upon leukemic transformation. Clonal hierarchy analysis revealed that STAT3 mutations represented the dominant clone in 30% of AML cases, but were subclonal in MDS and CMML. Most were missense mutations located at the SH2 domain, Y640F being the most common. STAT3 mutation was accompanied by co-existing mutations in all cases, most frequently SRSF2, TET2, ASXL1, and SETBP1. STAT3 mutations were usually associated with morphologic dysplasia, increased blasts, and monosomy 7/del7q. With a median follow-up of 24.5 months, 21 patients died, 6 had persistent disease, and 5 achieved complete remission after stem cell transplantation. CONCLUSIONS: STAT3 mutation is present in various MNs, but not in MPN. It is often an early event or occurs upon leukemic transformation, suggesting an important role in the pathogenesis and progression of MNs by activating JAK-STAT pathway. It may help identify a subset of patients with MNs who may benefit from targeted therapy.

6.
BMJ Open Qual ; 13(2)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816006

RESUMO

BACKGROUND: This service evaluation describes the rapid implementation of self-monitoring of blood pressure (SMBP) into maternity care at a tertiary referral centre during the COVID-19 pandemic. It summarises findings, identifies knowledge gaps and provides recommendations for further research and practice. INTERVENTION: Pregnant and postpartum women monitored their blood pressure (BP) at home, with instructions on actions to take if their BP exceeded pre-determined thresholds. Some also conducted proteinuria self-testing. DATA COLLECTION AND ANALYSIS: Maternity records, app data and staff feedback were used in interim evaluations to assess process effectiveness and guide adjustments, employing a Plan-Do-Study-Act and root cause analysis approach. RESULTS: Between March 2020 and August 2021, a total of 605 women agreed to self-monitor their BP, including 10 women with limited English. 491 registered for telemonitoring (81.2%). 21 (3.5%) took part in urine self-testing. Engagement was high and increased over time with no safety issues. Biggest concerns related to monitor supply and postnatal monitoring. In December 2020, SMBP was integrated into the standard maternity care pathway. CONCLUSIONS: This project demonstrated successful integration of SMBP into maternity care. Early stakeholder engagement and clear guidance were crucial and community midwifery support essential. Supplying BP monitors throughout pregnancy and post partum could improve the service and fully digitised maternity records would aid data collection. More research is needed on SMBP in the postnatal period and among non-English speakers. These findings support efforts to implement app-supported self-monitoring and guide future research.


Assuntos
COVID-19 , Melhoria de Qualidade , SARS-CoV-2 , Humanos , Feminino , Gravidez , COVID-19/epidemiologia , Adulto , Reino Unido , Medicina Estatal/organização & administração , Monitorização Ambulatorial da Pressão Arterial/métodos , Pandemias , Autocuidado/métodos , Telemedicina
7.
Eur J Pharmacol ; 974: 176615, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38685306

RESUMO

MicroRNA-29a (miR-29a) has been suggested to serve a potential protective function against Parkinson's disease (PD); however, the exact molecular mechanisms remain elusive. This study explored the protective role of miR-29a in a cellular model of PD using SH-SY5Y cell lines through iTRAQ-based quantitative proteomic and biochemistry analysis. The findings showed that using a miR-29a mimic in SH-SY5Y cells treated with 1-methyl-4-phenylpyridinium (MPP+) significantly decreased cell death and increased mitochondrial membrane potential. It also reduced mitochondrial reactive oxygen species (ROS) and the production of α-synuclein. Subsequent heatmap analysis using iTRAQ-based quantitative proteomics revealed remarkably contrasting protein expression profiles for 882 genes when comparing the groups treated with miR-29a mimic plus MPP + against the control group treated solely with MPP+. The KEGG pathway analysis of these 882 genes indicated the substantial role of miR-29a in the PD pathway (P = 1.58x10-5) and highlighted its function in mitochondrial genes. Furthermore, treatment with a miR-29a mimic in SH-SY5Y cells reduced the levels of GSK-3ß, phosphorylated GSK-3ß, and cleaved caspase-7 following exposure to MPP+. The miR-29a mimic also upregulated the expressions of α-synuclein clearance proteins FYCO1 and Rab7 in this cellular PD model, thereby inhibiting the production of α-synuclein. Luciferase activity analysis confirmed the specific binding of miR-29a to the 3' untranslated region (3'UTR) of GSK-3ß, leading to its repression. Our findings demonstrated miR-29a's neuroprotective role in mitochondrial function and highlighted its potential to inhibit ROS and α-synuclein production, offering possible therapeutic avenues for PD treatment.


Assuntos
Glicogênio Sintase Quinase 3 beta , MicroRNAs , Doença de Parkinson , Espécies Reativas de Oxigênio , alfa-Sinucleína , Humanos , 1-Metil-4-fenilpiridínio/toxicidade , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Linhagem Celular Tumoral , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , MicroRNAs/genética , MicroRNAs/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Espécies Reativas de Oxigênio/metabolismo
8.
J Food Sci ; 89(6): 3618-3628, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685872

RESUMO

In this study, a porous coordination network zirconium-porphyrin-based nanoparticle with oxygen vacancies (OVs) was prepared using acetic acid and benzoic acid as modulators via a simple hydrothermal method. The presence of OVs was confirmed by various characterization methods and was found to enhance oxygen uptake and activation. This resulted in the generation of more reactive peroxyl radicals (•O2 -) and led to an improved oxidase (OXD) mimetic activity. Additionally, it promoted 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) oxidation, with a low Km value of 0.07 mM and a high Vmax of 1.47 × 10-7 M·s-1. As aflatoxin B1 (AFB1) inhibits the Pt@PCN-222-ABTS nanozyme system, a colorimetric probe for AFB1 detection was constructed. The limit of detection (LOD) was 0.074 µg·L-1. This research presents a novel approach for designing a nanozymatic-based colorimetric method to analyze trace AFB1 residues in food.


Assuntos
Aflatoxina B1 , Colorimetria , Oxirredutases , Oxigênio , Porfirinas , Zircônio , Colorimetria/métodos , Aflatoxina B1/análise , Zircônio/química , Oxigênio/química , Porfirinas/química , Oxirredutases/metabolismo , Oxirredutases/química , Estruturas Metalorgânicas/química , Oxirredução , Limite de Detecção , Contaminação de Alimentos/análise , Nanopartículas/química
9.
JAMA Intern Med ; 184(6): 619-628, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587819

RESUMO

Importance: Recurrent urinary tract infection (UTI) is a common debilitating condition in women, with limited prophylactic options. d-Mannose has shown promise in trials based in secondary care, but effectiveness in placebo-controlled studies and community settings has not been established. Objective: To determine whether d-mannose taken for 6 months reduces the proportion of women with recurrent UTI experiencing a medically attended UTI. Design, Setting, and Participants: This 2-group, double-blind randomized placebo-controlled trial took place across 99 primary care centers in the UK. Participants were recruited between March 28, 2019, and January 31, 2020, with 6 months of follow-up. Participants were female, 18 years or older, living in the community, and had evidence in their primary care record of consultations for at least 2 UTIs in the preceding 6 months or 3 UTIs in 12 months. Invitation to participate was made by their primary care center. A total of 7591 participants were approached, 830 responded, and 232 were ineligible or did not proceed to randomization. Statistical analysis was reported in December 2022. Intervention: Two grams daily of d-mannose powder or matched volume of placebo powder. Main Outcomes and Measures: The primary outcome measure was the proportion of women experiencing at least 1 further episode of clinically suspected UTI for which they contacted ambulatory care within 6 months of study entry. Secondary outcomes included symptom duration, antibiotic use, time to next medically attended UTI, number of suspected UTIs, and UTI-related hospital admissions. Results: Of 598 women eligible (mean [range] age, 58 [18-93] years), 303 were randomized to d-mannose (50.7%) and 295 to placebo (49.3%). Primary outcome data were available for 583 participants (97.5%). The proportion contacting ambulatory care with a clinically suspected UTI was 150 of 294 (51.0%) in the d-mannose group and 161 of 289 (55.7%) in the placebo group (risk difference, -5%; 95% CI, -13% to 3%; P = .26). Estimates were similar in per protocol analyses, imputation analyses, and preplanned subgroups. There were no statistically significant differences in any secondary outcome measures. Conclusions and Relevance: In this randomized clinical trial, daily d-mannose did not reduce the proportion of women with recurrent UTI in primary care who experienced a subsequent clinically suspected UTI. d-Mannose should not be recommended for prophylaxis in this patient group. Trial Registration: isrctn.org Identifier: ISRCTN13283516.


Assuntos
Manose , Recidiva , Infecções Urinárias , Humanos , Infecções Urinárias/prevenção & controle , Feminino , Manose/uso terapêutico , Método Duplo-Cego , Pessoa de Meia-Idade , Adulto , Idoso
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124100, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484642

RESUMO

Peroxidase (POD)-mimicking nanozymes have got great progress in the sensing field, but most nanozyme assaying systems are built with a single-signal output mode, which is vulnerable to the effect of different factors. Thus, establishment of a dual-signal output mode is necessary for acquiring dependable and durable performance. This work described an Fe doped noradrenaline-based carbon dots and Prussian blue (Fe,NA-CDs/PB) nanocomposite as a POD-like nanozyme and modified gold nanoparticles (AuNPs) for the colorimetric and surface-enhanced Raman scattering (SERS) dual-mode sensor of Pb(II) in traditional Chinese medicine samples. With 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 3,3',5,5'-tetramethylbenzidine (TMB) as the substrates, it was found that the addition of Pb(II) inhibited the POD-like activity of Fe,NA-CDs/PB and AuNPs, so it was used for colorimetric and SERS dual-mode assays. The POD-like activity was shown to be a "ping-pong" catalytic mechanism, whereas the addition of Pb(II) produced noncompetitive inhibition with modulatory effects on Fe,NA-CDs/PB. The linear response range for colorimetric and SERS sensor detection of Pb(II) was 0.01-1.00 mg/L with the detection limit of 5 µg/L and 8 µg/L, respectively. This dual-mode detection system shows excellent selectivity. More importantly, the Pb(II) in traditional Chinese medicine samples have successfully assayed with good recovery from 90.4 to 108.9 %.


Assuntos
Colorimetria , Nanopartículas Metálicas , Ouro , Chumbo , Medicina Tradicional Chinesa , Carbono , Oxirredutases , Peroxidase , Íons , Peróxido de Hidrogênio
11.
Luminescence ; 39(2): e4684, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38332470

RESUMO

This study reports a sensitive and selective colorimetric approach for the analysis of dopamine (DA) based on CeO2 @ZIF-8/Cu-CDs laccase-like nanozymes activity. The CeO2 @ZIF-8/Cu-CDs was synthesized using cerium oxide (CeO2 ) and copper-doped carbon dots (Cu-CDs) with 2-methylimidazole by a facilely hydrothermal approach. The CeO2 @ZIF-8/Cu-CDs exhibited excellent laccase-like nanozymes activity and can oxidize the colorless substrate (DA) to red product with 4-aminoantipyrine as the chromogenic agent. The Michaelis-Menten constant (Km ) and the maximal velocity (Vmax ) of CeO2 @ZIF-8/Cu-CDs are 0.20 mM and 1.48 µM/min, respectively. The detection method has a linear range of 0.05-7.5 µg/mL and a detection limit as low as 8.5 ng/mL with good reproducibility. The developed colorimetric sensor was applied to rapid and precise quantitative evaluation of DA levels in serum and urine samples. This study presents a new approach for detecting biological molecules by utilizing the controlled regulation of nanozymes' laccase-like activity.


Assuntos
Cobre , Dopamina , Lacase , Colorimetria , Reprodutibilidade dos Testes , Carbono
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123865, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38219613

RESUMO

In this work, a facile synthesis method for dopamine carbon dots-based Au nanoparticles (DA-CDs/AuNPs) by seed gold method was reported as the surface enhanced Raman scattering (SERS) booster. DA-CDs with rich in surface functional groups was synthesized using dopamine, citric acid and ethylenediamine as precursors by a facile hydrothermal method, and can be used as the capping agents and reducing agents for the synthesis of DA-CDs/AuNPs. Due to the electromagnetic "hot spots" effect, DA-CDs/AuNPs with core-shell structure exhibited strong SERS activity. Based on the specific interaction of DA-CDs/AuNPs and fenamidone, a detection method of fenamidone was established with a low detection limit of 0.05 µg/mL. Finally, the SERS sensor was successfully applied to the detection of fenamidone in fruit with recoveries between 90.6 % and 98.7 %. The method here proposed can be reliably applied for fenamidone detection on fruits.

13.
J Control Release ; 365: 905-918, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092256

RESUMO

Diabetic wound treating remains a challenging due to bacterial infections, oxidative stress, tissue hypoxia, and high glucose levels. Herein, a multi-enzyme-like activities nanocomposite (Mo,Fe/Cu,I-Ag@GOx) was designed and anchored to a multifunctional fluorescence hydrogel. The nanozyme gel, loaded with glucose-oxidase (GOx), exhibits intrinsic GOx, peroxidase (POD)-, oxidase (OXD)-, catalase (CAT)- and superoxide dismutase (SOD)-like activities with pH-switchable glucose-initiated cascade reaction for diabetic wound healing. In the first cascade-reaction, initiated by GOx, the nanozyme gel catalyzes glucose and O2 into gluconic acid and H2O2 to further generate superoxide anion radical (O2·-) and hydroxyl radicals (·OH) to eradicate bacteria. In the second cascade-reaction, as the wound pH changes alkalescent microenvironment, the nanozyme gel simulates SOD to transform O2·- into O2 and H2O2, and then decomposes endogenous and exogenous H2O2 into O2 via CAT-like activity to reduce oxidative stress and alleviate hypoxia. The gel by calcium ion (Ca2+) cross-linked sodium alginate (SA) and chitosan (CS) containing nanozyme was constructed with injectability, adhesion and fluorescence properties, as well as beneficial biocompatible. Importantly, the water/alcohol solubility of the nanozyme gel allows it to be used as a dressing without causing secondary injury to the wound. The multifunctional fluorescence hydrogel exhibits efficiently promote pro-angiogenesis and bacteria-infected wound healing.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Peróxido de Hidrogênio , Glucose Oxidase , Superóxido Dismutase , Glucose , Hipóxia , Oxigênio , Concentração de Íons de Hidrogênio , Antibacterianos
14.
J Hazard Mater ; 465: 133126, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056252

RESUMO

Perusing metal-based redox nanozyme offers new opportunity for pollutant removal and biosensor, but ultrasound (US)-driven laccase-like nanozyme remains a significant challenge, especially in combination with defect engineering strategy. Herein, the Cu2Ov@Ce-TCPP was synthesized by doping Ce3+ on the surface of Cu2O nanocube and then coating with the porphyrin sonosensitizer. The Ce-doped porphyrin metal-structure in nanozyme was demonstrated to generate oxygen vacancy defects, which could obviously promote the laccase-like activity of Cu2Ov@Ce-TCPP nanozyme under US. XPS characterization and density functional theory (DFT) theoretical calculation revealed that the ultrasonic stimulation is beneficial to accelerate the electron transfer rate and O2 adsorption to improve catalytic activity, and Cu2Ov@Ce-TCPP nanozyme exhibits low adsorption energy and activation energy due to the presence of oxygen defect site, resulting in high laccase-like activity. The interaction between Ce atom and porphyrin structure also improved the sonocatalytic ability of the nanozyme. Meanwhile, Cu2Ov@Ce-TCPP nanozyme has been used for detecting and degrading a series of phenolic compounds. The detection adrenaline method has a linear range of 3.3-1000 µM and a detection limit as low as 0.96 µM with good reproducibility. The developed US-enhancing and recyclable laccase-like nanozyme system provides a promising strategy for the oxidation and detection of phenolic compounds.


Assuntos
Lacase , Porfirinas , Lacase/metabolismo , Epinefrina , Reprodutibilidade dos Testes , Fenóis , Oxirredução , Oxigênio , Porfirinas/química
15.
Tissue Eng Regen Med ; 21(2): 291-308, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37903982

RESUMO

BACKGROUND: The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period. METHODS: Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT-PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7. RESULTS: Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7-21 days showed even better performance for hESCs but was ineffective for hiPSCs. CONCLUSION: The differentiation efficiency of cells could be improved by determining the optimal treatment period. Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration.


Assuntos
Células-Tronco Mesenquimais , Células-Tronco Pluripotentes , Humanos , Osteogênese , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular , Peptídeos/farmacologia , Peptídeos/metabolismo
16.
J Diabetes Investig ; 15(1): 44-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38031656

RESUMO

AIMS/INTRODUCTION: Serum amyloid A (SAA) is an acute phase reactive protein that plays a vital role in the early diagnosis, risk prediction, efficacy observation and prognosis evaluation of infectious diseases. This study aimed to assess the association between SAA levels and the prognosis of patients with coronavirus disease 2019 (COVID-19) and diabetes. MATERIALS AND METHODS: We carried out this retrospective cohort study from March 2022 to May 2022. The population was stratified by tertiles of SAA levels: low (<8.5 mg/L), medium (8.5-36 mg/L) and high (>36 mg/L). The primary outcome was whether the patient developed severe COVID-19, and secondary outcomes included the need for invasive mechanical ventilation and length of hospital stay. Logistic regression analyses were carried out to identify risk factors affecting the prognosis of patients with COVID-19 and diabetes. RESULTS: We analyzed 910 diabetes patients with COVID-19. The median age of the patients was 69 years, and 52.3% were men. As SAA levels increased, the proportion of severe COVID-19 (6.3% vs 7.3% vs 22.8%, P < 0.001) and the proportion of invasive mechanical ventilation also increased among the three groups. Patients with high SAA levels had a longer length of hospital stay compared with patients with medium SAA and low SAA levels. Univariate logistic regression analysis showed that SAA >36 mg/L further increased the odds ratio to 4.423 (P < 0.001) for the development of severe COVID-19 compared with low SAA. Multivariate logistic regression analysis, adjusted for age and sex, confirmed that SAA >36 mg/L remained an independent risk factor for the development of severe COVID-19 (adjusted odds ratio 3.038, P < 0.001). CONCLUSIONS: SAA levels are strongly associated with poor prognosis in patients with COVID-19 and diabetes.


Assuntos
COVID-19 , Diabetes Mellitus , Masculino , Humanos , Idoso , Feminino , COVID-19/diagnóstico , COVID-19/epidemiologia , Proteína Amiloide A Sérica/análise , Proteína Amiloide A Sérica/metabolismo , Estudos Retrospectivos , Prognóstico , Proteínas de Fase Aguda/análise , Diabetes Mellitus/epidemiologia
17.
Phytochem Anal ; 35(1): 135-145, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37743673

RESUMO

INTRODUCTION: Agarwood, a fragrant resinous wood mainly formed by Aquilaria spp., is used worldwide as a natural fragrance and traditional medicine. A large amount of Aquilaria sinensis (Lour.) Gilg leaves are underutilised during the process of the agarwood industry, and the development of A. sinensis leaves as tea has recently attracted more and more attention. However, the small molecule profile of A. sinensis leaves and their bioactivities has been rarely reported. OBJECTIVE: To conduct a rapid untargeted liquid chromatography-mass spectrometry (LC-MS) analysis of A. sinensis leaves with a molecular networking (MN) strategy and evaluate its antioxidant and antidiabetic value. METHOD: A MN-assisted tandem mass spectrometry (MS/MS) analysis strategy was used to investigate the small molecule profile of A. sinensis leaves. Additionally, the integration of antioxidant and α-glucosidase inhibitory assays with MN analysis was executed to expeditiously characterise the bioactive compounds for potential prospective application. RESULTS: Five main chemical groups including phenol C-glycosides, organic acids, 2-(2-phenylethyl) chromones, benzophenone O-glycosides and flavonoids were rapidly revealed from the A. sinensis leaves. Eighty-one compounds were provisionally identified by comparing their MS/MS fragments with canonical pathways. The featured xanthone C-glycosides and benzophenone C-glycosides were recognised as the primary components of A. sinensis leaves. Several dimers and a trimer of mangiferin were reported firstly in A. sinensis leaves. Furthermore, 17 and 14 potential bioactive molecules were rapidly annotated from antioxidant and α-glucosidase inhibitory fraction, respectively. CONCLUSION: Our findings will help expand the utilisation of A. sinensis leaves and thus promote the high-quality development of agarwood industry.


Assuntos
Espectrometria de Massas em Tandem , Thymelaeaceae , Antioxidantes/farmacologia , alfa-Glucosidases , Flavonoides/química , Glicosídeos , Thymelaeaceae/química , Benzofenonas
18.
J Pharm Biomed Anal ; 239: 115922, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134706

RESUMO

The amorphous Cu-containing phosphomolybdate (Cu-PTs) composite with high peroxidase (POD)-like activity at neutral conditions was explored as biosensors for raloxifene (RAF) detection. The strong attraction between negatively charged Cu-PTs and positively charged substrates 3,3',5,5'-tetramethylbenzidine (TMB), as well as the acceleration of the conversion of active Cu+/Cu2+ by the Cu/W bimetallic redox couples were demonstrated to play significant roles in POD-like activity in physiological environment. When RAF is presence, it can bind to the surface of Cu-PTs and changes the chemical signal on the material surface, leading to the decreased POD-like activity. Based on this, a colorimetric method was established for the sensitive assay of RAF with a lower limit of detection (LOD) of 0.025 mg/L and good recovery from 90.13% to 108.9%. This work paves a new way to design a POD-like colorimetric protocol for tracing RAF in pharmaceutical products and environmental samples.


Assuntos
Técnicas Biossensoriais , Cloridrato de Raloxifeno , Colorimetria/métodos , Peroxidase , Peroxidases , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio
19.
Br J Gen Pract ; 74(738): e34-e40, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38154945

RESUMO

BACKGROUND: Sleep restriction therapy (SRT) is a behavioural therapy for insomnia. AIM: To conduct a process evaluation of a randomised controlled trial comparing SRT delivered by primary care nurses plus a sleep hygiene booklet with the sleep hygiene booklet only for adults with insomnia disorder. DESIGN AND SETTING: A mixed-methods process evaluation in a general practice setting. METHOD: Semi-structured interviews were conducted in a purposive sample of patients receiving SRT, the practice nurses who delivered the therapy, and also GPs or practice managers at the participating practices. Qualitative data were explored using framework analysis, and integrated with nurse comments and quantitative data, including baseline Insomnia Severity Index score and serial sleep efficiency outcomes to investigate the relationships between these. RESULTS: In total, 16 patients, 13 nurses, six practice managers, and one GP were interviewed. Patients had no previous experience of behavioural therapy, needed flexible appointment times, and preferred face-to-face consultations; nurses felt prepared to deliver SRT, accommodating patient concerns, tailoring therapy, and negotiating sleep timings despite treatment complexity and delays between training and intervention delivery. How the intervention produced change was explored, including patient and nurse interactions and patient responses to SRT. Difficulties maintaining SRT, negative attitudes towards treatment, and low self-efficacy were highlighted. Contextual factors, including freeing GP time, time constraints, and conflicting priorities for nurses, with suggestions for alternative delivery options, were raised. Participants who found SRT a positive process showed improvements in sleep efficiency, whereas those who struggled did not. CONCLUSION: SRT was successfully delivered by practice nurses and was generally well received by patients, despite some difficulties delivering and applying the intervention in practice.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Adulto , Humanos , Distúrbios do Início e da Manutenção do Sono/terapia , Sono , Higiene do Sono/fisiologia , Medicina de Família e Comunidade , Atenção Primária à Saúde , Resultado do Tratamento
20.
Nat Aging ; 3(11): 1387-1400, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37884767

RESUMO

DNA methylation deregulation at partially methylated domains (PMDs) represents an epigenetic signature of aging and cancer, yet the underlying molecular basis and resulting biological consequences remain unresolved. We report herein a mechanistic link between disrupted DNA methylation at PMDs and the spatial relocalization of H3K9me3-marked heterochromatin in aged hematopoietic stem and progenitor cells (HSPCs) or those with impaired DNA methylation. We uncover that TET2 modulates the spatial redistribution of H3K9me3-marked heterochromatin to mediate the upregulation of endogenous retroviruses (ERVs) and interferon-stimulated genes (ISGs), hence contributing to functional decline of aged HSPCs. TET2-deficient HSPCs retain perinuclear distribution of heterochromatin and exhibit age-related clonal expansion. Reverse transcriptase inhibitors suppress ERVs and ISGs expression, thereby restoring age-related defects in aged HSPCs. Collectively, our findings deepen the understanding of the functional interplay between DNA methylation and histone modifications, which is vital for maintaining heterochromatin function and safeguarding genome stability in stem cells.


Assuntos
Células-Tronco Hematopoéticas , Heterocromatina , Heterocromatina/genética , Células-Tronco Hematopoéticas/metabolismo , Metilação de DNA/genética
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