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1.
Analyst ; 149(13): 3651-3660, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38814120

RESUMO

Monitoring methods for beta-lactam (ß-lactam) antibiotics, especially for ampicillin (AMP), with simple operation and sensitivity for realtime applications are highly required. To address this need, antioxidant carbon dots (E-CDs) with excellent fluorescence properties were synthesized using citric acid and ethylenediamine as raw materials. With a quantum yield of 81.97%, E-CDs exhibited a specific and sensitive response to ˙OH. The quenched fluorescence of E-CDs by the formed ˙OH could be restored through a competition reaction with AMP. Leveraging the signal-quenching strategy of E-CDs, H2O2, and Fe2+, a fluorescence signal-on strategy was developed using AMP as the fluorescence recovery agent for the sensitive detection of AMP. The mechanism of the quenching of E-CDs by ˙OH was attributed to the damaging effect of ˙OH on E-CDs. Under optimal conditions, the detection limit of this method for AMP was determined to be 0.38 µg mL-1. This method was successful in drug quality control and the spiked detection of AMP in lake water, milk, and sea cucumber, presenting a viable option for convenient and rapid antibiotic monitoring methods.


Assuntos
Ampicilina , Carbono , Limite de Detecção , Pontos Quânticos , Espectrometria de Fluorescência , Carbono/química , Ampicilina/análise , Ampicilina/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Animais , Antioxidantes/análise , Antioxidantes/química , Leite/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Radical Hidroxila/química , Radical Hidroxila/análise , Antibacterianos/análise , Antibacterianos/química , Corantes Fluorescentes/química , Ácido Cítrico/química , Fluorescência , Etilenodiaminas
2.
J Fluoresc ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300482

RESUMO

Diabetic mellitus management extends beyond blood glucose monitoring to the essential task of mitigating the overexpression of reactive oxygen species (ROS), particularly vital for cellular repair, especially within the nervous system. Herein, antioxidant carbon dots (Arg-CDs) were designed and prepared using anhydrous citric acid, L-arginine, and ethylenediamine as sources through a hydrothermal method. Arg-CDs exhibited excellent scavenging ability to 2,2-Diphenyl-1-picrylhydrazyl (DPPH∙), and fluorescence response to hydroxyl radicals (∙OH), a characteristic representative of reactive oxygen species (ROS). Assisted by glucose oxidase and Fe2+, Arg-CDs showed a sensitive and selective response to glucose. The quenching mechanism of Arg-CDs by formed ∙OH was based on the static quenching effect (SQE). The analytical performance of this method for glucose detection encompassed a wide linear range (0.3-15 µM), a low practical limit of detection (0.1 µM) and practical applicability for blood glucose monitoring. In an in vitro model employing glial cells (BV2 cells), it was observed that high glucose medium led to notable cellular damage ascribed to the excessive ROS production from hyperglycemia. The diminished and apoptotic glial cells were gradually recovered by adding increased contents of Arg-CDs. This work illustrates a promising area that designs effective carbon dots with antioxidant capacity for the dual applications of detection and cell repairing based on the utilization of antioxidant activity.

3.
J Fluoresc ; 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37530930

RESUMO

The establishment of a convenient and effective detection method for doxycycline (DC) holds significant importance in drug monitoring and drug residue assessment. In this work, carbon quantum dots (CQDs) with excellent and stable luminescence performance (the quantum yield of CQDs was 21.8%) were synthesized by the melting method and employed as probes to monitor the fluorescence intensity variations before and after the introduction of DC. A fluorescence analytical method based on the internal filtration effect (IFE) was developed for DC determination. The mechanism of DC quenching CQDs was verified using fluorescence lifetime tests, absorption spectroscopy, and evaluation of internal filtration parameters. After optimizing experimental conditions, it was found that the DC concentration (CDC) exhibited a good linear relationship with the fluorescence quenching efficiency ((F0-F)/F0) of CQDs in the range of 5-30 µM. The fitted linear equation was Y = 0.01249*CDC+0.03625, R2 = 0.9987, and the detection limit was 2.343 µM (n = 8). This developed method has been successfully applied to accurately determine DC concentrations in both doxycycline hydrochloride tablets and human serum samples. It stands out for its simplicity, rapidity, and acceptable detection performance. Due to its advantages, this method holds great promise for application in the biomedical field for monitoring DC drug concentrations and ensuring quality control.

4.
Chem Pharm Bull (Tokyo) ; 71(11): 812-818, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37704432

RESUMO

Tyrosinase (TYR) plays a pivotal role in the biosynthesis of melanin, and its activity level holds critical implications for vitiligo, melanoma cancer, and food nutritional value. The sensitive determination of TYR activity is of great significance for both fundamental research and clinical investigations. In this work, we successfully synthesized silicon-doped carbon quantum dots (Si-CQDs) through a one-pot hydrothermal method with trans-aconitic acid as carbon source and N-[3-(trimethoxysilyl)propyl]ethylenediamine as the dopant, exhibiting remarkable fluorescence quantum yield (QY) and photostability. Correspondingly, Si-CQDs were used as a probe to construct a sensitive, rapid, and user-friendly fluorescence method for TYR detection. The method relied on the oxidation of isoprenaline (ISO) by TYR, where Si-CQDs were employed as a highly efficient probe. The testing mechanism was the internal filtering effect (IFE) observed between Si-CQDs and the oxidative system of ISO and TYR. Under the optimized conditions, the fluorescence strategy exhibited a detection range of 0.05-2.0 U/mL for TYR with a limit of detection (LOD) of 0.041 U/mL. Furthermore, we successfully demonstrated the accurate determination of TYR levels in human serum, showcasing the promising potential of this method in various practical scenarios.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Humanos , Monofenol Mono-Oxigenase , Carbono , Silício , Técnicas Biossensoriais/métodos , Nitrogênio , Espectrometria de Fluorescência/métodos
5.
Anal Bioanal Chem ; 413(6): 1605-1614, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33515273

RESUMO

Effective and simultaneous monitoring of the abnormal expression of certain microRNAs (miRNAs), especially for miRNA-21 and miRNA-155, can indicate drug resistance in lung cancer. In this work, T7 exonuclease (T7 Exo)-assisted target recycling amplification coupled with the extensive fluorescence quenching of graphene oxide (GO) was designed for the simultaneous detection of miRNA-21 and miRNA-155 using FAM- and ROX-labeled single-strand DNA probes. Through this method, the variable emission intensities of FAM and ROX caused by the introduction of miRNA-21 and miRNA-155, respectively, were obtained with high sensitivity. The method exhibited excellent analytical performance for simultaneous detection of miRNA-21 and miRNA-155 without cross-interference. The linear range was from 0.005 nM to 5 nM over three orders of magnitude, with detection limits as low as 3.2 pM and 4.5 pM for miRNA-21 and miRNA-155, respectively. Furthermore, the recovery (92.49-103.67%) and relative standard deviation (RSD < 4.8%) of the standard addition test of miRNA-21 and miRNA-155 in human plasma suggested the potential for drug resistance warning in clinical practice via this simple strategy. A homogeneous T7 Exo-assisted signal amplification combined with GO quenching platform was developed for accurate, sensitive and simultaneous analysis of miRNA-21 and miRNA-155 for drug resistance warning in lung cancer. This simple method exhibited a wide linear range and low LODs for miR-21 and miR-155.


Assuntos
Técnicas Biossensoriais , Exodesoxirribonucleases/metabolismo , Neoplasias Pulmonares/sangue , MicroRNAs/análise , Sondas de DNA/química , Polarização de Fluorescência , Grafite/química , Humanos , Limite de Detecção , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasma/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos
6.
Chem Pharm Bull (Tokyo) ; 68(7): 628-634, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32336694

RESUMO

Facile and effective detection of dopamine (DA) plays a significant role in current clinical applications. Substantially, special optical nanomaterials are important for fabricating easy-to-control, cheap, selective, and portable fluorescence DA sensors with superior performance. Herein, carbon dots (CDs) prepared from melting method were applied as signal to establish a simple but effective fluorescence strategy for DA determination based on the enzymatic activity of acid phosphatase (ACP), which induces DA to form polydopamine (pDA). The formed pDA caused by the enzymatic oxidization of ACP toward DA can interact with CDs through the inner filter effect. Such behavior effectively quenched the CDs' fluorescence. The degree of fluorescence quenching of CDs was positively correlated with the DA content. Under the optimized reaction conditions, the proposed fluorescence method exhibited a comparable analytical performance with other DA sensors with good selectivity. Furthermore, this method has been successfully applied to detect DA in DA hydrochloride injection and human serum samples. It shows that this method features potential practical application value and is expected to be used in clinical research.


Assuntos
Fosfatase Ácida/metabolismo , Dopamina/análise , Dopamina/metabolismo , Fluorescência , Indóis/metabolismo , Polímeros/metabolismo , Fosfatase Ácida/química , Carbono/química , Indóis/química , Oxirredução , Tamanho da Partícula , Polímeros/química , Pontos Quânticos/química , Espectrometria de Fluorescência , Propriedades de Superfície
7.
Mikrochim Acta ; 185(5): 260, 2018 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-29680977

RESUMO

Amino-modified carbon dots (C-dots) with positively charged surface were prepared. They display strong blue fluorescence and are shown to act as quenchers of the green fluorescence of FAM-labeled ssDNA such as the F-probe used in this work that was immobilized on the C-dots. On the addition of highly negatively charged heparin (Hep), it will interact with the C-dots and displace the F-probe from C-dots. Once the F-probe is displaced by Hep, its green fluorescence is restored. The intrinsic blue fluorescence of the C-dots remains stable after addition of Hep. Thus, a signal-on ratiometric fluorometric assay was developed for the ultra-sensitive detection of Hep. The underlying mechanisms of quenching and recovery are discussed. Under optimized conditions, the recovery of the ratiometric fluorescence of the system composed of C-dots and quenched F-probe is proportional to the Hep concentration in the range of 0.01-2.0 µg·mL-1 (= 0.00125-0.25 U·mL-1). The method was successfully applied to the determination of Hep in spiked serum samples. Graphical abstract Schematic of a signal-on ratiometric fluorometric method for the ultra-sensitive detection of heparin on the basis of the displacement and fluorescence enhancement of adsorbed FAM-labeled ssDNA from amino-modified carbon dots (C-dots) by heparin.


Assuntos
Bioensaio , Carbono/química , Fluorometria , Heparina/análise , Animais , DNA , Corantes Fluorescentes , Fluorometria/métodos , Heparina/sangue , Limite de Detecção , Pontos Quânticos , Coelhos
8.
Sensors (Basel) ; 18(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072628

RESUMO

Simple and effective methods for the detection of the level of blood glucose are closely linked to the monitoring of people's health. In the study, MnO2 nanosheets with absorption range of 300 nm~500 nm and obvious yellow color were easily prepared and applied to detect glucose through their absorbance and color. The proposed method is based on the fact that a specific concentration of glucose can be quantitatively transformed into hydrogen peroxide (H2O2) under the catalytic effect of glucose oxidase. Based on the redox reaction of MnO2 with H2O2, yellow MnO2 can be converted into colorless Mn2+ to monitor the concentration of glucose. Under optimal conditions, a simple and effective visual assay for the sensitive and reliable detection of glucose was developed. The linear range was estimated to the range from 0 µM to 100 µM, with a detection limit of 12.8 µM. Furthermore, the proposed colorimetric assay based on MnO2 nanosheets can effectively detect blood glucose of clinical serum samples with accuracy and convenience.


Assuntos
Glicemia/análise , Colorimetria/métodos , Compostos de Manganês/química , Nanoestruturas/química , Óxidos/química , Glicemia/química , Glicemia/metabolismo , Glucose Oxidase/metabolismo , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Limite de Detecção
10.
Anal Chem ; 86(5): 2711-8, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24524671

RESUMO

A green approach is proposed for in situ growth of porous platinum nanoparticles on graphene oxide (PtNPs/GO). The resulting nanocomposite has been proven to function as peroxidase mimetics that can catalyze the reaction of peroxidase substrate in the presence of hydrogen peroxide. On the basis of the peroxidase-like activity, we used the PtNPs/GO as a signal transducer to develop a colorimetric assay for the direct detection of cancer cells. By using folic acid as a recognition element, a total of 125 cancer cells (MCF-7) can be distinguished by naked-eye observation. We envision that this nanomaterial could be used as a power tool for a wide range of potential applications in biotechnology and medicine.


Assuntos
Colorimetria , Grafite/química , Nanopartículas Metálicas , Platina/química , Humanos , Microscopia de Força Atômica , Óxidos/química
11.
Sensors (Basel) ; 14(3): 5611-21, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24658623

RESUMO

OBJECTIVE: To develop a convenient; sensitive; accurate; and economical technique for genotyping of hepatitis B viruses (HBVs). METHODS: The mercapto-modified B1; B2; C1; and C2-specific genotyping probes consisted of two probes for each HBV genotype that served as a double verification system. These probes were fixed on the surface of No. 1; 2; 3; and 4 gold electrodes; respectively; via Au-S bonds. Different charge generated by the binding of RuHex to phosphate groups of the DNA backbone before and after hybridization was used for distinguishing the different genotypes. RESULTS: During hybridization with genotype B; the charges detected at the No. 1 and 2 electrodes were significantly increased; while the charge at the No. 3 and 4 electrodes did not change significantly. During hybridization with genotype C; the charges detected at No. 3 and 4 electrodes were significantly increased; while the signals remained unchanged at the No. 1 and 2 electrodes. During hybridization with mixed genotypes (B and C); the charges detected at all four electrodes were significantly increased. The linear range of detection was 10(-7) to 10(-10) mol/L and the sensitivity for detecting mixed B (10%) or C (10%). CONCLUSIONS: Rapid genotyping of HBVs based on electrochemical sensing is simple, has good specificity; and can greatly reduce the cost. This method can be used for sensitive detection of mixed B and C HBV genotypes.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Técnicas de Genotipagem/métodos , Vírus da Hepatite B/genética , Sequência de Bases , Sondas de DNA/metabolismo , DNA Viral/análise , DNA Viral/genética , Eletrodos , Genótipo
12.
Artigo em Inglês | MEDLINE | ID: mdl-38294507

RESUMO

The present study aims to explore the therapeutic effect of Stefin B on gouty arthritis (GA) and the polarization of macrophages in mice. Stefin B-overexpressed or knockdown M0 macrophages were constructed. The GA model was established in mice by injecting 25 mg/mL MSU, followed by a single injecting of Stefin B-overexpressing adenovirus vector (GA model + Stefin B OE) or an empty vector (GA model + Stefin B OE NC). Stefin B was found lowly expressed in M1 macrophages. CD206 was markedly upregulated and IL-10 release was signally increased in Stefin B-overexpressed macrophages. In gouty arthritis mice, marked redness and swelling were observed in the ankle joint. Dramatical infiltration of inflammatory cells was observed in the GA model and GA model + Stefin B OE NC groups, which was suppressed in the Stefin B OE group. Increased proportion of F4/80+CD86+ cells observed in GA mice was markedly repressed by Stefin B overexpression, accompanied by the declined level of Caspase-1 and IL-17. Collectively, Stefin B alleviated the GA in mice by inducing the M2 polarization of macrophages.

13.
Adv Healthc Mater ; 13(7): e2302873, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041688

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) infection and compromised immunity are the severe complications associated with implantation surgery in diabetes mellitus. Enhancing the antibacterial and immunomodulatory properties of implants represents an effective approach to improve the osseointegration of implant in diabetes mellitus. Herein, guanidination carbon dots (GCDs) with antibacterial and immunoregulatory functions are synthesized. The GCDs demonstrate killing effect on MRSA without detectable induced resistance. Additionally, they promote the polarization of macrophages from the M1 to M2 subtype, with the inhibiting pro-inflammatory cytokines and promoting anti-inflammatory factors. Correspondingly, GCDs are immobilized onto sulfonated polyether ether ketone (SP@GCDs) using a polyvinyl butyraldehyde (PVB) coating layer through soaking-drying technique. SP@GCDs maintain stable antibacterial efficacy against MRSA for six consecutive days and retain the immunomodulatory function, while also possessing the long-term storage stability and biocompatibility of more than 6 months. Moreover, SP@GCDs significantly promote the proliferation and mineralization of osteoblasts. SP@GCDs facilitate osteogenesis through immunoregulatory. Additionally, SP@GCDs exert stable antibacterial and immune regulatory functions in implantation site of a diabetes rat, effectively promoting implant osseointegration regardless of the MRSA infection. These findings provide valuable insights into implant modification through designing nanomaterials with multifunction for enhancing osseointegration of diabetes mellitus, suggesting the promising clinical application prospects.


Assuntos
Anti-Infecciosos , Benzofenonas , Diabetes Mellitus , Staphylococcus aureus Resistente à Meticilina , Polímeros , Ratos , Animais , Osseointegração , Carbono , Polietilenoglicóis/farmacologia , Anti-Infecciosos/farmacologia , Cetonas/farmacologia , Antibacterianos/farmacologia , Osteogênese , Propriedades de Superfície
14.
Talanta ; 278: 126451, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38917549

RESUMO

Developing water-soluble nanomaterials with high photoluminescence emission and high yield for biological analysis and imaging is urgently needed. Herein, water-soluble blue emitting silicon and nitrogen co-doped carbon dots (abbreviated as Si-CDs) of a high photoluminescence quantum yield of 80 % were effectively prepared with high yield rate (59.1 %) via one-step hydrothermal treatment of N-[3-(trimethoxysilyl)propyl]ethylenediamine (DAMO) and trans-aconitic acid. Furthermore, the Si-CDs demonstrate environmental robustness, photo-stability and biocompatibility. Given the importance of the potentially abnormal levels of acid phosphatase (ACP) in cancer diagnosis, developing a reliable and sensitive ACP measurement method is of significance for clinical research. The Si-CDs unexpectedly promote the catalytic oxidation of ACP on dopamine (DA) to polydopamine under acidic conditions through the produced reactive oxygen species (ROS). Correspondingly, a fluorescence response strategy using Si-CDs as the dual functions of probes and promoting enzyme activity of ACP on catalyzing DA was constructed to sensitively determine ACP. The quantitative analysis of ACP displayed a linear range of 0.1-60 U/L with a detection limit of 0.056 U/L. The accurate detection of ACP was successfully achieved in human serum through recovery tests. As a satisfactory fluorescent probe, Si-CDs were successfully applied to fluorescent imaging of A549 cells in cytoplasmic with long-term and safe staining. The Si-CDs have the dual properties of outstanding fluorescent probes and auxiliary oxidase activity, indicating their great potential in multifunctional applications.

15.
Analyst ; 138(24): 7341-6, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24162097

RESUMO

The fabrication of a facile, sensitive, and versatile immunosensor for the quantification of metallothionein-3 (MT-3) is proposed in this work. The K3[Fe(CN)6]-chitosan-glutaraldehyde (K-CS-GA) conjugate prepared from K3[Fe(CN)6], chitosan and glutaraldehyde was employed as the redox-active signal source. Carbon nanodots (C-dots) were coupled with Nafion to form the nanocomposite architecture layer to carry antibodies (Abs). C-dots enhanced the electrochemical response of the proposed immunosensor to improve the detection sensitivity. The fabrication steps of the immunosensor were characterized using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Antigen determination was achieved via the decreased current response of the K3[Fe(CN)6] caused by the insulated coupled antigen. The detected signals were proportional to the logarithm of the concentrations of MT-3 ranging from 5 pg mL(-1) to 20 ng mL(-1) with a detection limit of 2.5 pg mL(-1) in PBS. The proposed immunosensor showed high sensitivity, good selectivity and reproducibility. Furthermore, detection results using real serum samples showed the immunosensor's potential applications in clinical diagnostics.


Assuntos
Anticorpos/química , Técnicas Eletroquímicas/métodos , Ferricianetos/química , Polímeros de Fluorcarboneto/química , Imunoensaio/métodos , Proteínas do Tecido Nervoso/análise , Metalotioneína 3 , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Proteínas do Tecido Nervoso/imunologia , Oxirredução
16.
Medicine (Baltimore) ; 102(15): e33489, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058031

RESUMO

The phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway has gradually become a new target for the treatment of osteoarthritis (OA). Numerous studies of PI3K/Akt signaling in OA have been published in the past few years. By analyzing these research characteristics and qualities, we aimed to reveal the current research focus and emerging trends in PI3K/Akt signaling in OA. We searched the Web of Science database for relevant articles concerning the PI3K/Akt signaling pathway in OA published from inception to October 31, 2022. The following data were extracted: author name, article title, keywords, topic, publication country/region, institution, publication journal, journal impact factor, number of times cited, and H-index. VOSviewer and Excel 2019 were used to conduct the bibliometric study and visualize the analysis. A total of 374 publications were included in this study. In all selected articles, "orthopedics" was the dominant topic (252 of 374, 67.38%). The most productive year was 2021. Frontiers in Pharmacology published the most articles. The People's Republic of China has published the most articles worldwide. The top 5 keywords were "OA," "expression," "apoptosis," "chondrocytes," and "inflammation." The keywords "autophagy," "mitochondrial dysfunction," "inflammatory response," "cartilage degeneration," and "network pharmacology" have increased in recent years. Our study showed a growing trend in published articles related to the PI3K/Akt signaling pathway in OA. Inflammatory response, cartilage degeneration, and apoptosis remain central topics in the field. Research on autophagy, mitochondrial dysfunction, and network pharmacology is on the rise, and the focus on PI3K/Akt will continue to increase.


Assuntos
Osteoartrite , Proteínas Proto-Oncogênicas c-akt , Humanos , Fosfatidilinositol 3-Quinases , Transdução de Sinais , Bibliometria
17.
J Mater Chem B ; 11(32): 7696-7706, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37458409

RESUMO

Infections caused by Gram-negative bacteria still pose a clinical challenge. Although nanomaterials have been developed for antibacterial treatments, a systematic evaluation of the mechanisms and intervention models of antibacterial materials toward Gram-negative bacteria is still lacking. Herein, antibacterial quaternized carbon dots (QCDs) were synthesized via a one-step melting method using anhydrous citric acid and diallyl dimethyl ammonium chloride (DDA). The QCDs exhibited effective broad-spectrum antibacterial activity and enhanced inhibitory ability towards Gram-negative bacteria. The antibacterial mechanism of the QCDs with respect to Gram-negative bacteria was investigated through the characterization of bacterial morphology changes, the absorption modes of the QCDs on bacteria, and the potential generation of reactive oxygen species by the QCDs. The QCDs showed low toxicity in different cells, and did not cause hemolysis. The QCDs were administered via intraperitoneal injection to treat acute peritonitis in mice infected with E. coli. Routine blood examination, magnetic resonance imaging, and pathological analysis were undertaken and it was found that, similar to the positive control group treated with gentamicin sulfate, the QCDs exhibited a therapeutic effect that eliminated infection and inflammation. This study explores a controllable synthetic strategy for the synthesis of active carbon dots with antibacterial activity, a material that is a promising candidate for new treatments of Gram-negative bacterial infections.


Assuntos
Anti-Infecciosos , Peritonite , Animais , Camundongos , Escherichia coli , Carbono/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias Gram-Negativas , Bactérias , Peritonite/tratamento farmacológico
18.
Anal Chim Acta ; 1279: 341789, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827683

RESUMO

There has been significant interest in the preparation and versatile applications of carbon dots (CDs) due to their immense potential value in sensors and imaging. In this work, silicon-doped green carbon dots (Si-CDs) with high quantum yield and rich epoxypropyl were effectively synthesized. Given the clinical diagnostic importance of abnormal levels of tyrosinase (TYR), sensitive detection of TYR is significant for clinical research. A fluorescence signal-off strategy with Si-CDs as probe was constructed to determine TYR based on the oxidation of dopamine by TYR. The detection ranges of this method were 0.01-1.5 and 10-30 U/mL with the detection limit of 0.0046 U/mL, the lower limit of quantification (LLOQ) was 0.01 U/mL, and TYR was successfully and accurately monitored in human serum. Additionally, due to the role of lysosomes in cellular regulatory processes, including TYR levels and fluorescence stability characteristics of Si-CDs in acidic conditions, it was envisaged to use Si-CDs as probe to establish real-time monitoring of lysosomes. According to fluorescence colocation analysis, Si-CDs had intrinsic lysosomal targeting ability to HepG2 and L-02 (with Pearson correlation coefficients were 0.90 and 0.91, respectively). The targeting of Si-CDs to lysosomes was due to the acidophilic effect of the epoxypropyl on its surface.


Assuntos
Monofenol Mono-Oxigenase , Pontos Quânticos , Humanos , Carbono , Dopamina , Oxirredução , Corantes Fluorescentes , Nitrogênio
19.
Front Surg ; 9: 1050347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36895848

RESUMO

Purpose: To determine the incidence and risk factors of deep vein thrombosis (DVT) of lower extremities at admission in elderly Chinese patients with femoral neck fracture, and to establish and evaluate a new DVT predictor based on these risk factors. Methods: Patients who were hospitalized from January 2018 to December 2020 at three independent centers were reviewed. According to the results of lower extremities vascular ultrasound at admission, they were divided into DVT group and non-DVT group. Single and multivariate logistic regression analysis were applied to identify independent risk factors for DVT occurrence, and then a prediction formula for DVT based on the risk factors was developed. The new predictive index of DVT was calculated by the formula. Receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic value of different factors and the new predictive index. Results: There were 203 elder patients were included in the final analysis after application of the exclusion criteria. Thirty seven patients (18.2%) were diagnosed as DVT by ultrasound, including 33 patients (89.2%) of peripheral type, 1 patient (2.7%) of central type and 3 patients (8.1%) of mixed type.Multivariate logistic regression analysis showed that four factors including injured side, hemoglobin, fibrinogen, d-dimer were the independent risk factors for the incidence of DVT. On this basis, a new formula for DVT predictive factor was constructed: New predictive index = 0.895 * injured side (right = 1, left = 0) + 0.899 * hemoglobin (<109.5 g/L = 1, > 109.5 g/L = 0) + 1.19 * fibrinogen (>4.24 g/L = 1, < 4.24 g/L = 0) + 1.221* d-dimer (>2.4 mg/L = 1, < 2.4 mg/L = 0). The AUC value of this new developed index was 0.735. Conclusions: This work showed that the incidence of DVT in elderly patients with femoral neck fracture in China was high at admission. New DVT predictive value can be used as an effective diagnosis strategy for evaluation of thrombosis at admission.

20.
ACS Appl Mater Interfaces ; 14(47): 52579-52598, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36380598

RESUMO

Patients suffering diabetic bone defects still need some new and effective strategies to achieve enhanced prognostic effects. Although medical implants are the common treatment of bone defects, the excessive oxidative stress and high risk of bacterial infection in diabetes mellitus lead to a higher risk of implant failure. To improve the healing ability of diabetic bone defects, herein, polyetheretherketone (PEEK) was modified through a developed layer-by-layer (LBL) construction strategy to obtain multifunctional PEEK (SP@(TA-GS/PF)*3) by the assembly of tannic acid (TA), gentamicin sulfate (GS) and Pluronic F127 (PF127) on the basis of prepared porous PEEK through sulfonation (SPEEK). The prepared SP@(TA-GS/PF)*3 exhibited sustained antimicrobial activity and enhanced the differentiation of osteoblast (MC3T3-E1) for needed osteogenesis. Moreover, SP@(TA-GS/PF)*3 scavenged excessive oxidative stress to promote the growth of H2O2 damaged HUVEC with enhanced secretion of VEGF for neovascularization. In addition, the remarkable in vivo outcomes of angiogenesis and osseointegration were revealed by the subcutaneous implant model and bone tissue implant model in diabetic rats, respectively. The in vitro and in vivo results demonstrated that modified PEEK with multifunction can be an attractive tool for enhancing bone integration under diabetic conditions, underpinning the clinical application potential of modified implants for diabetic osseointegration.


Assuntos
Antioxidantes , Diabetes Mellitus Experimental , Ratos , Animais , Antioxidantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Benzofenonas/farmacologia , Cetonas/farmacologia , Polietilenoglicóis/farmacologia , Osseointegração , Osteogênese , Osso e Ossos , Antibacterianos/farmacologia , Propriedades de Superfície
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