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1.
Anal Chem ; 96(32): 13308-13316, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39078110

RESUMO

NAD(P)H: quinone oxidoreductase-1 (NQO1) plays critical roles in antioxidation and abnormally overexpresses in tumors. Developing a fast and sensitive method of monitoring NQO1 will greatly promote cancer diagnosis in clinical practice. This study introduces a transformative colorimetric detection strategy for NQO1, harnessing an innovative competitive substrate mechanism between NQO1 and a new NADH oxidase (NOX) mimic, cobalt-nitrogen-doped carbon nanozyme (CoNC). This method ingeniously exploits the differential consumption of NADH in the presence of NQO1 to modulate the generation of H2O2 from CoNC catalysis, which is then quantified through a secondary, peroxidase-mimetic cascade reaction involving Prussian blue (PB) nanoparticles. This dual-stage reaction framework not only enhances the sensitivity of NQO1 detection, achieving a limit of detection as low as 0.67 µg mL-1, but also enables the differentiation between cancerous and noncancerous cells by their enzymatic activity profiles. Moreover, CoNC exhibits exceptional catalytic efficiency, with a specific activity reaching 5.2 U mg-1, significantly outperforming existing NOX mimics. Beyond mere detection, CoNC serves a dual role, acting as both a robust mimic of cytochrome c reductase (Cyt c) and a cornerstone for enzymatic regeneration, thereby broadening the scope of its biological applications. This study not only marks a significant step forward in the bioanalytical application of nanozymes but also sets the stage for their expanded use in clinical diagnostics and therapeutic monitoring.


Assuntos
Colorimetria , NAD(P)H Desidrogenase (Quinona) , NADH NADPH Oxirredutases , NAD(P)H Desidrogenase (Quinona)/metabolismo , NAD(P)H Desidrogenase (Quinona)/química , Humanos , NADH NADPH Oxirredutases/metabolismo , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Complexos Multienzimáticos/metabolismo , Complexos Multienzimáticos/química , Cobalto/química , Carbono/química , Biomimética , Limite de Detecção , Nitrogênio/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Ferrocianetos/química , NAD/metabolismo , NAD/química
2.
J Immunol ; 209(10): 1960-1972, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36426951

RESUMO

Aspergillus fumigatus is an important opportunistic fungal pathogen and causes invasive pulmonary aspergillosis in conditions with compromised innate antifungal immunity, including chronic granulomatous disease, which results from inherited deficiency of the superoxide-generating leukocyte NADPH oxidase 2 (NOX2). Derivative oxidants have both antimicrobial and immunoregulatory activity and, in the context of A. fumigatus, contribute to both fungal killing and dampening inflammation induced by fungal cell walls. As the relative roles of macrophage versus neutrophil NOX2 in the host response to A. fumigatus are incompletely understood, we studied mice with conditional deletion of NOX2. When NOX2 was absent in alveolar macrophages as a result of LysM-Cre-mediated deletion, germination of inhaled A. fumigatus conidia was increased. Reducing NOX2 activity specifically in neutrophils via S100a8 (MRP8)-Cre also increased fungal burden, which was inversely proportional to the level of neutrophil NOX2 activity. Moreover, diminished NOX2 in neutrophils synergized with corticosteroid immunosuppression to impair lung clearance of A. fumigatus. Neutrophil-specific reduction in NOX2 activity also enhanced acute inflammation induced by inhaled sterile fungal cell walls. These results advance understanding into cell-specific roles of NOX2 in the host response to A. fumigatus. We show that alveolar macrophage NOX2 is a nonredundant effector that limits germination of inhaled A. fumigatus conidia. In contrast, reducing NOX2 activity only in neutrophils is sufficient to enhance inflammation to fungal cell walls as well as to promote invasive A. fumigatus. This may be relevant in clinical settings with acquired defects in NOX2 activity due to underlying conditions, which overlap risk factors for invasive aspergillosis.


Assuntos
Aspergillus fumigatus , Neutrófilos , Camundongos , Animais , NADPH Oxidase 2/genética , Macrófagos , Inflamação
3.
Thorax ; 78(2): 211-213, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36261274

RESUMO

Rosai-Dorfman disease (RDD) is a non-malignant condition mainly manifesting as a proliferation of histiocytes in lymph nodes. Endotracheal RDD (ERDD) with an acute onset presentation is extremely rare. There are few case reports of ERDD mainly concerning its pathology, diagnostics and bronchoscopic treatment, without providing sufficient clinical information from a comprehensive perspective. As a novel and challenging technique, tracheal resection and reconstruction (TRR) with spontaneous-ventilation video-assisted thoracoscopic surgery (SV-VATS) has been reported as feasible and safe in highly selected patients, but few centres have shared their experience with this approach. This case-based discussion includes not only practical issues in the management of a life-threatening ERDD patient, but also specialists' views on the management of acute obstructive airway, and the surgeons' reflection on TRR with SV-VATS.


Assuntos
Obstrução das Vias Respiratórias , Histiocitose Sinusal , Humanos , Histiocitose Sinusal/diagnóstico , Histiocitose Sinusal/cirurgia , Histiocitose Sinusal/patologia , Traqueia/cirurgia , Traqueia/patologia , Histiócitos/patologia
4.
Chemphyschem ; 24(16): e202300216, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37232190

RESUMO

Achieving solar light-driven photocatalytic overall water splitting is the ideal and ultimate goal for solving energy and environment issues. Photocatalytic Z-scheme overall water splitting has undergone considerable development in recent years; specific approaches include a powder suspension Z-scheme system with a redox shuttle and a particulate sheet Z-scheme system. Of these, a particulate sheet has achieved a benchmark solar-to-hydrogen efficiency exceeding 1.1 %. Nevertheless, owing to intrinsic differences in the components, structure, operating environment, and charge transfer mechanism, there are several differences between the optimization strategies for a powder suspension and particulate sheet Z-scheme. Unlike a powder suspension Z-scheme with a redox shuttle, the particulate sheet Z-scheme system is more like a miniaturized and parallel p/n photoelectrochemical cell. In this review, we summarize the optimization strategies for a powder suspension Z-scheme with a redox shuttle and particulate sheet Z-scheme. In particular, attention has been focused on choosing appropriate redox shuttle and electron mediator, facilitating the redox shuttle cycle, avoiding redox mediator-induced side reactions, and constructing a particulate sheet. Challenges and prospects in the development of efficient Z-scheme overall water splitting are also briefly discussed.

5.
Med Sci Monit ; 29: e940783, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37545114

RESUMO

BACKGROUND Acute pancreatitis, a sudden inflammation of the pancreas, can result in severe complications. The presence and volume of ascites, an abnormal accumulation of fluid in the abdomen, has been linked to disease severity. Our study investigates ascites volume, quantified via abdominal CT scans, as a potential predictive tool for disease severity. MATERIAL AND METHODS In this retrospective analysis, patients diagnosed with acute pancreatitis were evaluated. Patients were categorized into groups with and without ascites, with comparisons made regarding clinical characteristics. We further compared the mean ascitic volume against various outcome parameters in patients with ascites. Ascites volume and other predictive systems were assessed through receiver operating characteristic (ROC) curves, with the area under the ROC curve (AUC) for different predictive systems being analyzed. RESULTS The ascites group had higher severity scores and related serological indexes (P<0.05 for all). Among patients with ascites, a significant correlation was observed between ascites volume and outcome parameters (P<0.05 for all). The area under the ROC curve for predicting severe acute pancreatitis was 0.896, with 93% sensitivity and 79% specificity. Ascites volume yielded the highest diagnostic odds ratio (53.1; 95% confidence interval: 13.2,199.6). CONCLUSIONS Early-stage acute pancreatitis patients with ascites are indicative of severe illness and poor prognosis. An increase in ascites volume correlates with adverse clinical outcomes, thus highlighting the significance of ascites volume as a prognostic marker. This underscores the importance of abdominal CT in measuring ascites volume to predict disease severity.


Assuntos
Ascite , Pancreatite , Humanos , Ascite/diagnóstico por imagem , Estudos Retrospectivos , Índice de Gravidade de Doença , Doença Aguda , Pancreatite/complicações , Tomografia Computadorizada por Raios X/métodos , Abdome , Curva ROC , Prognóstico , Valor Preditivo dos Testes
6.
BMC Anesthesiol ; 23(1): 54, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797665

RESUMO

OBJECTIVES: The erector spinae plane (ESP) block is a newly defined regional anesthesia technique first described in 2016. The aim of this meta-analysis is to assess the efficacy of ESP block in improving analgesia following lumbar surgery. METHODS: PubMed, EMBASE, Cochrane Library, and Web of Science were searched for randomized controlled trials (RCTs) that compared the analgesic efficacy of the ESP block with non-block care for lumbar surgery from inception 3 August 2021. The primary outcomes were postoperative opioid consumption and pain scores during the first 24 h. Postoperative pain was measured as pain at rest and on movement at postoperative 0, 4, 8, 12, and 24 h expressed on a visual analog scale (VAS), where 0 = no pain and 10 = the most severe pain. RESULTS: 11 studies involving 775 patients were included in our analysis. The use of ESP block significantly decreased 24-h opioid consumption (WMD, -8.70; 95% CI, -10.48 to -6.93; I2 = 97.5%; P < 0.001) compared with the non-block. Moreover, ESP block reduced pain scores at postoperative time-points up to 24 h. ESP block also prolonged the time to first analgesic request (WMD = 6.93; 95% CI: 3.44 to 10.43, I2 = 99.8%; P < 0.001). There was less PONV with ESP block versus non-block group (RR, 0.354; 95% CI, 0.23 to 0.56; I2 = 25.2%; P < 0.001), but no difference in pruritus. CONCLUSIONS: ESP block provides less opioid consumption and PONV, lower pain scores, and longer time to first analgesic request in patients undergoing lumbar surgery compared to general anesthesia alone.


Assuntos
Analgesia , Bloqueio Nervoso , Humanos , Analgésicos Opioides/uso terapêutico , Bloqueio Nervoso/métodos , Náusea e Vômito Pós-Operatórios , Manejo da Dor/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Analgesia/métodos
7.
J Asian Nat Prod Res ; 25(1): 1-10, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35023415

RESUMO

Five new compounds, named gingerol A (1a and 1b), gingerol B (2), diphenylheptane glycoside A (3) and diphenylheptane glycoside B (4), were isolated from the acetone extract of Zingiberis Rhizoma Recens. The structures of new compounds were elucidated on the basis of spectroscopic methods including UV, IR, 1D NMR, 2D NMR and HR-ESI-MS. Compounds 2-4 could significantly decrease the apoptosis rate and increase the survival rate of human normal lung epithelial cells (BEAS-2B) at the concentration of 10 µM.


Assuntos
Catecóis , Extratos Vegetais , Humanos , Glicosídeos
8.
Nano Lett ; 22(6): 2554-2560, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35157470

RESUMO

Tuning the local confinement of reaction intermediates is of pivotal significance to promote C-C coupling for enhancing the selectivity for multicarbon (C2+) products toward CO2 electroreduction. Herein, we have gained insights into the confinement effect of local CO concentration for enhanced C-C coupling over core-shell Ag@Cu catalysts by tuning the pore diameters within porous Cu shells. During CO2 electroreduction, the core-shell Ag@Cu catalysts with an average pore diameter of 4.9 nm within the Cu shells (Ag@Cu-p4.9) exhibited the highest Faradaic efficiency of 73.7% for C2+ products at 300 mA cm-2 among the three Ag@Cu catalysts. Finite-element-method simulations revealed that the pores with a diameter of 4.9 nm in Cu conspicuously enhanced the local CO concentration. On the basis of in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy measurements, Ag@Cu-p4.9 exhibited the highest surface coverage of adsorbed CO intermediates with a linear adsorption configuration due to the confinement effect, thus facilitating C-C coupling.

9.
Anal Chem ; 94(38): 13261-13268, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36103467

RESUMO

Inspired by the architecture of single-atom catalysts, where the monodispersed metal atoms are widely distributed but stabilized by various coordination circumstances, the biomimetic design and synthesis of metalloporphyrin-containing nanocages have been demonstrated in this study. The nanocages were fabricated through a coordination-driven self-assembly process, and the Mn(III) porphyrin-based one was found to have exclusively peroxidase-like activity at pH 6.0 with neither oxidase nor catalase-like activity under the routine conditions. Benefiting from this, we demonstrated the wide applicability and convenient usage of an Mn(III)-containing supramolecular nanocage (Mn-PC) in the one-step detection of H2O2, sarcosine, and glucose through various oxidase-involved reactions, with a satisfactory detection limit and eligible specificity. Real samples including H2O2 in lens care solution, sarcosine in human urine, and glucose in human serum were also assayed, showing an adequate recovery rate. Such a specific activity originates from the super-consistent microstructure of each catalytic unit, which means that the active site of manganese porphyrin was "protected" by the confinement of the nanocage. This also helps to sustain the super long-term activity even after 545 days of storage. Furthermore, the intrinsic electronic structure of the Mn(III)-containing supramolecular nanocage endows the ability in electrochemical detection of H2O2 and glucose. Our smart design toward the supramolecular nanocages with a defined structure and quantity contributes to the construction of the ingenious sensing platform and has guiding significance for architectural design of nanozymes.


Assuntos
Metaloporfirinas , Porfirinas , Catalase , Domínio Catalítico , Glucose/química , Humanos , Peróxido de Hidrogênio/química , Manganês/química , Metaloporfirinas/química , Peroxidase/metabolismo , Peroxidases , Porfirinas/química , Sarcosina
10.
Blood ; 135(12): 891-903, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31951647

RESUMO

Leukocyte reduced NADP (NADPH) oxidase plays a key role in host defense and immune regulation. Genetic defects in NADPH oxidase result in chronic granulomatous disease (CGD), characterized by recurrent bacterial and fungal infections and aberrant inflammation. Key drivers of hyperinflammation induced by fungal cell walls in CGD are still incompletely defined. In this study, we found that CGD (CYBB-) neutrophils produced higher amounts of leukotriene B4 (LTB4) in vitro after activation with zymosan or immune complexes, compared with wild-type (WT) neutrophils. This finding correlated with increased calcium influx in CGD neutrophils, which was restrained in WT neutrophils by the electrogenic activity of NADPH oxidase. Increased LTB4 generation by CGD neutrophils was also augmented by paracrine cross talk with the LTB4 receptor BLT1. CGD neutrophils formed more numerous and larger clusters in the presence of zymosan in vitro compared with WT cells, and the effect was also LTB4- and BLT1-dependent. In zymosan-induced lung inflammation, focal neutrophil infiltrates were increased in CGD compared with WT mice and associated with higher LTB4 levels. Inhibiting LTB4 synthesis or antagonizing the BLT1 receptor after zymosan challenge reduced lung neutrophil recruitment in CGD to WT levels. Thus, LTB4 was the major driver of excessive neutrophilic lung inflammation in CGD mice in the early response to fungal cell walls, likely by a dysregulated feed-forward loop involving amplified neutrophil production of LTB4. This study identifies neutrophil LTB4 generation as a target of NADPH oxidase regulation, which could potentially be exploited therapeutically to reduce excessive inflammation in CGD.


Assuntos
Parede Celular/imunologia , Fungos/imunologia , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Infiltração de Neutrófilos/genética , Neutrófilos/metabolismo , Receptores do Leucotrieno B4/metabolismo , Animais , Cálcio , Modelos Animais de Doenças , Suscetibilidade a Doenças , Camundongos , Micoses/genética , Micoses/imunologia , Micoses/metabolismo , Micoses/microbiologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Neutrófilos/patologia , Oxirredução , Estresse Oxidativo , Ligação Proteica , Transdução de Sinais
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