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1.
Dermatol Online J ; 30(1)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38762856

RESUMO

Generalized pustular psoriasis is a rare variant of psoriasis. Evidence recommending generalized pustular psoriasis treatment with secukinumab is limited. This report aims to evaluate the use of secukinumab in two patients with generalized pustular psoriasis. The standard treatment regimen for secukinumab was as follows: 300mg subcutaneously once weekly in weeks 0-4, followed by 300mg every four weeks. The efficacy was evaluated by analyzing the psoriasis area and severity index (PASI) and dermatology life quality index (DLQI). One patient had generalized pustular psoriasis, which had developed from palmoplantar pustulosis over 12 years. The second patient was an adolescent with recurrent generalized pustular psoriasis. The first patient achieved PASI-75 response by week 3 and both PASI-90 and a DLQI score of 0 were observed by week 8. The second patient achieved PASI-75 response by week 4 and complete clinical resolution, except for nail changes, and a DLQI of 0 by week 8, without any adverse events.


Assuntos
Anticorpos Monoclonais Humanizados , Psoríase , Índice de Gravidade de Doença , Humanos , Psoríase/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Masculino , Adolescente , Feminino , Anticorpos Monoclonais/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Qualidade de Vida , Adulto
2.
Mar Drugs ; 22(5)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38786605

RESUMO

Chemical investigation of marine fungus Nigrospora oryzae SYSU-MS0024 cultured on solid-rice medium led to the isolation of three new alkaloids, including a pair of epimers, nigrosporines A (1) and B (2), and a pair of enantiomers, (+)-nigrosporine C (+)-3, and (-)-nigrosporine C (-)-3, together with eight known compounds (4-11). Their structures were elucidated based on extensive mass spectrometry (MS) and 1D/2D nuclear magnetic resonance (NMR) spectroscopic analyses and compared with data in the literature. The absolute configurations of compounds 1-3 were determined by a combination of electronic circular dichroism (ECD) calculations, Mosher's method, and X-ray single-crystal diffraction technique using Cu Kα radiation. In bioassays, compound 2 exhibited moderate inhibition on NO accumulation induced by lipopolysaccharide (LPS) on BV-2 cells in a dose-dependent manner at 20, 50, and 100 µmol/L and without cytotoxicity in a concentration of 100.0 µmol/L. Moreover, compound 2 also showed moderate acetylcholinesterase (AChE) inhibitory activities with IC50 values of 103.7 µmol/L. Compound 5 exhibited moderate antioxidant activity with EC50 values of 167.0 µmol/L.


Assuntos
Alcaloides , Ascomicetos , Inibidores da Colinesterase , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Animais , Camundongos , Ascomicetos/química , Linhagem Celular , Óxido Nítrico/metabolismo , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Estrutura Molecular , Acetilcolinesterase/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Lipopolissacarídeos/farmacologia
3.
J Crit Care ; 82: 154793, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38548515

RESUMO

BACKGROUND: Electrolyte disturbances are highly heterogeneous and severely affect the prognosis of critically ill patients. Our study was to determine whether data-driven phenotypes of seven electrolytes have prognostic relevance in critically ill patients. METHODS: We extracted patient information from three large independent public databases, and clustered the electrolyte distribution of ICU patients based on the extreme value, median value and coefficient of variation of electrolytes. Three plausible clinical phenotypes were calculated using K-means clustering algorithm as the basic clustering method. MIMIC-IV was considered a training set, and two others have been designated as verification set. The robustness of the model was then validated from different angles, providing dynamic and interactive visual charts for more detailed characterization of phenotypes. RESULTS: 15,340, 12,445 and 2147 ICU patients with electrolyte records during early ICU stay in MIMIC-IV, eICU-CRD and AmsterdamUMCdb were enrolled. After clustering, three reasonable and interpretable phenotypes are defined as α, ß and γ according to the order of clusters. The α and γ phenotype, with significant differences in electrolyte distribution and clinical variables, higher 28-day mortality and longer length of ICU stay (p < 0.001), was further demonstrated by robustness analysis. The α phenotype has significant kidney injury, while the ß phenotype has the best prognosis. In addition, the assignment methods of the three phenotypes were developed into a web-based tool for further verification and application. CONCLUSIONS: Three different clinical phenotypes were identified that correlated with electrolyte distribution and clinical outcomes. Further validation and characterization of these phenotypes is warranted.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Fenótipo , Desequilíbrio Hidroeletrolítico , Humanos , Feminino , Masculino , Desequilíbrio Hidroeletrolítico/diagnóstico , Desequilíbrio Hidroeletrolítico/sangue , Pessoa de Meia-Idade , Prognóstico , Idoso , Internet , Tempo de Internação , Análise por Conglomerados , Eletrólitos/sangue , Algoritmos
4.
Opt Lett ; 49(6): 1524-1527, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489441

RESUMO

Longitudinal detection of hemodynamic changes based on wearable devices is imperative for monitoring human healthcare. Photoacoustic effect is extremely sensitive to variations in hemoglobin. Therefore, wearable photoacoustic devices are apt to monitor human healthcare via the observation of hemodynamics. However, the bulky system and difficulties in miniaturizing and optimizing the imaging interface restrict the development of wearable photoacoustic devices for human use. In this study, we developed a wearable photoacoustic watch with a fully integrated system in a backpack that has a size of 450 mm × 300 mm × 200 mm and an affordable weight of 7 kg for an adult to wear. The watch has a size of 43 mm × 30 mm × 24 mm, weighs 40 g, and features a lateral resolution of 8.7 µm, a field of view (FOV) of 3 mm in diameter, and a motorized adjustable focus for optimizing the imaging plane for different individuals. We recruited volunteers to wear the watch and the backpack and performed in vivo imaging of the vasculatures inside human wrists under the conditions of walking and human cuff occlusion to observe hemodynamic variations during different physiological states. The results suggest that the focus shifting capability of the watch makes it suitable for different individuals, and the compact and stable design of the entire system allows free movements of humans.


Assuntos
Técnicas Fotoacústicas , Dispositivos Eletrônicos Vestíveis , Adulto , Humanos , Diagnóstico por Imagem , Análise Espectral , Hemodinâmica
5.
Heliyon ; 10(6): e27035, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515673

RESUMO

Doxorubicin (DOX) possesses strong anti-tumor effects but is limited by its irreversible cardiac toxicity. The relationship between exercise, a known enhancer of cardiovascular health, and DOX-induced cardiotoxicity has been a focus of recent research. Exercise has been suggested to mitigate DOX's cardiac harm by modulating the Yes-associated protein (YAP) and Signal transducer and activator of transcription 3 (STAT3) pathways, which are crucial in regulating cardiac cell functions and responses to damage. This study aimed to assess the protective role of exercise preconditioning against DOX-induced cardiac injury. We used Sprague-Dawley rats, divided into five groups (control, DOX, exercise preconditioning (EP), EP-DOX, and verteporfin + EP + DOX), to investigate the potential mechanisms. Our findings, including echocardiography, histological staining, Western blot, and q-PCR analysis, demonstrated that exercise preconditioning could alleviate DOX-induced cardiac dysfunction and structural damage. Notably, exercise preconditioning enhanced the nuclear localization and co-localization of YAP and STAT3. Our study suggests that exercise preconditioning may counteract DOX-induced cardiotoxicity by activating the YAP/STAT3 pathway, highlighting a potential therapeutic approach for reducing DOX's cardiac side effects.

6.
Int J Biol Macromol ; 263(Pt 1): 130229, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38378110

RESUMO

Microbial glycosyltransferases efficiently synthesize glucosides and have garnered increasing interest. However, limited regioselectivity has impeded their broad application, particularly in the pharmaceutical industry. In this study, the UDP-glycosyltransferase YjiC from Bacillus licheniformis (BlYjiC) was engineered to achieve the bidirectional regioselective glycosylation of tyrosol and its derivatives. Initially, site-directed saturation mutagenesis was performed on two newly identified substrate-binding cavities in the acceptor pocket of BlYjiC to provide a comprehensive blueprint of the interplay between mutations and function (mutability landscape). Iterative saturation mutagenesis was performed, guided by the mutability landscape. Two highly regioselective mutants M6 (M112L/I325Y/L70R/Q136E/I67E/M77R) and M2' (M112D/I62L) were generated, exhibiting >99 % regioselectivity toward the alcoholic and phenolic hydroxyl of tyrosol, respectively, compared with the wild-type (product mixture: 51:49 %). Both mutants exhibited excellent regioselectivity toward several dihydroxy phenolic substrates, offering valuable biocatalysts for the regioselective synthesis of glucosides. Their application was confirmed in a short synthesis of salidroside (3.6 g/L) and icariside D2 (2.4 g/L), which exhibited near-perfect regioselectivity. This study provides valuable insights into future protein engineering of similar enzymes and opens new avenues for their practical applications.


Assuntos
Glucosídeos , Glicosiltransferases , Fenóis , Álcool Feniletílico/análogos & derivados , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Glicosilação , Glucosídeos/metabolismo
7.
Eur Stroke J ; : 23969873241232311, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353230

RESUMO

INTRODUCTION: Hemorrhagic stroke may cause changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP), which may influence the prognosis of patients. The aim of this study was to investigate the relationship between early ICP, CPP, and 28-day mortality in the intensive care unit (ICU) of patients with hemorrhagic stroke. PATIENTS AND METHODS: A retrospective study was performed using the Medical Information Mart for Intensive Care (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD), including hemorrhagic stroke patients in the ICU with recorded ICP monitoring. The median values of ICP and CPP were collected for the first 24 h of the patient's monitoring. The primary outcome was 28-day ICU mortality. Multivariable Cox proportional hazards models were used to analyze the relationship between ICP, CPP, and 28-day ICU mortality. Restricted cubic regression splines were used to analyze nonlinear relationships. RESULTS: The study included 837 patients with a 28-day ICU mortality rate of 19.4%. Multivariable analysis revealed a significant correlation between early ICP and 28-day ICU mortality (HR 1.08, 95% CI 1.04-1.12, p < 0.01), whereas early CPP showed no correlation with 28-day ICU mortality (HR 1.00, 95% CI 0.98-1.01, p = 0.57), with a correlation only evident when CPP < 60 mmHg (HR 1.99, 95% CI 1.14-3.48, p = 0.01). The study also identified an early ICP threshold of 16.5 mmHg. DISCUSSION AND CONCLUSION: Early ICP shows a correlation with 28-day mortality in hemorrhagic stroke patients, with a potential intervention threshold of 16.5 mmHg. In contrast, early CPP showed no correlation with patient prognosis.

8.
BMC Nephrol ; 25(1): 48, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321419

RESUMO

PURPOSE: This study aimed to investigate the association between cytochrome P450 (CYP) 3A4*22 and cytochrome P450 oxidoreductase (POR)*28 variations and the pharmacokinetics of tacrolimus. METHODS: Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science (SCI), MEDLINE, and Embase were systematically searched from inception to August 2022. The outcomes were weight-adjusted daily dose and dose-adjusted trough concentration (C0/Dose). RESULTS: The study included 2931 renal transplant recipients from 18 publications. Weight-adjusted daily dose of CYP3A4*1/*1 carriers was 0.04 (WMD = 0.04, 95% CI: 0.02 to 0.06), 0.03 (WMD = 0.03, 95% CI: 0.02 to 0.05), 0.02 (WMD = 0.02, 95% CI: 0.01 to 0.03), or 0.02 mg/kg/day (WMD = 0.02, 95% CI: 0.00 to 0.04) higher than CYP3A4*22 carriers in Caucasians at 1 month, 3 months, 6 months, or 12 months post-transplantation. Conversely, C0/Dose was lower for CYP3A4*1/*1 carriers at 3 days (SMD = -0.35, 95% CI: -0.65 to -0.06), 1 month (SMD = -0.67, 95% CI: -1.16 to -0.18), 3 months (SMD = -0.60, 95% CI: -0.89 to -0.31), 6 months (SMD = -0.76, 95% CI: -1.49 to -0.04), or 12 months post-transplantation (SMD = -0.69, 95% CI: -1.37 to 0.00). Furthermore, C0/Dose of POR*1/*1 carriers was 22.64 (WMD = 22.64, 95% CI: 2.54 to 42.74) or 19.41 (ng/ml)/(mg/kg/day) (WMD = 19.41, 95% CI: 9.58 to 29.24) higher than POR*28 carriers in CYP3A5 expressers at 3 days or 7 days post-transplantation, and higher in Asians at 6 months post-transplantation (SMD = 0.96, 95% CI: 0.50 to 1.43). CONCLUSIONS: CYP3A4*22 variant in Caucasians restrains the metabolism of tacrolimus, while POR*28 variant in CYP3A5 expressers enhances the metabolism of tacrolimus for renal transplant recipients. However, further well-designed prospective studies are necessary to substantiate these conclusions given some limitations.


Assuntos
Transplante de Rim , Tacrolimo , Humanos , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Imunossupressores , Estudos Prospectivos , Polimorfismo de Nucleotídeo Único , Transplantados , Genótipo
9.
BMC Med Res Methodol ; 24(1): 41, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365610

RESUMO

BACKGROUND: Missing data is frequently an inevitable issue in cohort studies and it can adversely affect the study's findings. We assess the effectiveness of eight frequently utilized statistical and machine learning (ML) imputation methods for dealing with missing data in predictive modelling of cohort study datasets. This evaluation is based on real data and predictive models for cardiovascular disease (CVD) risk. METHODS: The data is from a real-world cohort study in Xinjiang, China. It includes personal information, physical examination data, questionnaires, and laboratory biochemical results from 10,164 subjects with a total of 37 variables. Simple imputation (Simple), regression imputation (Regression), expectation-maximization(EM), multiple imputation (MICE) , K nearest neighbor classification (KNN), clustering imputation (Cluster), random forest (RF), and decision tree (Cart) were the chosen imputation methods. Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) are utilised to assess the performance of different methods for missing data imputation at a missing rate of 20%. The datasets processed with different missing data imputation methods were employed to construct a CVD risk prediction model utilizing the support vector machine (SVM). The predictive performance was then compared using the area under the curve (AUC). RESULTS: The most effective imputation results were attained by KNN (MAE: 0.2032, RMSE: 0.7438, AUC: 0.730, CI: 0.719-0.741) and RF (MAE: 0.3944, RMSE: 1.4866, AUC: 0.777, CI: 0.769-0.785). The subsequent best performances were achieved by EM, Cart, and MICE, while Simple, Regression, and Cluster attained the worst performances. The CVD risk prediction model was constructed using the complete data (AUC:0.804, CI:0.796-0.812) in comparison with all other models with p<0.05. CONCLUSION: KNN and RF exhibit superior performance and are more adept at imputing missing data in predictive modelling of cohort study datasets.


Assuntos
Algoritmos , Doenças Cardiovasculares , Humanos , Estudos de Coortes , Aprendizado de Máquina , Máquina de Vetores de Suporte , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia
10.
Opt Lett ; 49(4): 798-801, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359185

RESUMO

Optical resolution photoacoustic microscopy (OR-PAM) is a hybrid imaging method for visualizing organelles due to the high spatial resolution and abundant optical contrast. Usually, OR-PAM employs high numerical aperture (NA) objectives and high-frequency ultrasonic detectors to resolve three-dimensional (3D) microstructures of cells. Expansion microscopy (ExM) provides a nanoscale resolution by isotropically enlarging cells instead of utilizing ultrahigh NA objectives. In this Letter, we report the development of photoacoustic expansion microscopy (PA-ExM) that combines the advantages of OR-PAM and ExM for 3D organelle imaging using near-infrared light. We evaluate the performance of PA-ExM using label-free melanoma cells, where the image quality of melanosome distributions in expanded cells using a 40× objective is comparable to that of unexpanded cells using an oil-immersed 100× objective. The results suggest that PA-ExM possesses the great potential to study organelles.


Assuntos
Microscopia , Técnicas Fotoacústicas , Microscopia/métodos , Melanossomas , Técnicas Fotoacústicas/métodos , Análise Espectral , Imagem Multimodal
11.
Nat Commun ; 15(1): 891, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291026

RESUMO

Procaspase 9 is the initiator caspase for apoptosis, but how its levels and activities are maintained remains unclear. The gigantic Inhibitor-of-Apoptosis Protein BIRC6/BRUCE/Apollon inhibits both apoptosis and autophagy by promoting ubiquitylation of proapoptotic factors and the key autophagic protein LC3, respectively. Here we show that BIRC6 forms an anti-parallel U-shaped dimer with multiple previously unannotated domains, including a ubiquitin-like domain, and the proapoptotic factor Smac/DIABLO binds BIRC6 in the central cavity. Notably, Smac outcompetes the effector caspase 3 and the pro-apoptotic protease HtrA2, but not procaspase 9, for binding BIRC6 in cells. BIRC6 also binds LC3 through its LC3-interacting region, probably following dimer disruption of this BIRC6 region. Mutation at LC3 ubiquitylation site promotes autophagy and autophagic degradation of BIRC6. Moreover, induction of autophagy promotes autophagic degradation of BIRC6 and caspase 9, but not of other effector caspases. These results are important to understand how the balance between apoptosis and autophagy is regulated under pathophysiological conditions.


Assuntos
Apoptose , Proteínas Inibidoras de Apoptose , Apoptose/genética , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Caspases/metabolismo , Autofagia/genética , Ubiquitinação , Proteínas Mitocondriais/metabolismo
12.
Acta Pharmacol Sin ; 45(1): 125-136, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37684381

RESUMO

Acute kidney injury (AKI) is a worldwide public health problem characterized by the massive loss of tubular cells. However, the precise mechanism for initiating tubular cell death has not been fully elucidated. Here, we reported that phosphoglycerate mutase 5 (PGAM5) was upregulated in renal tubular epithelial cells during ischaemia/reperfusion or cisplatin-induced AKI in mice. PGAM5 knockout significantly alleviated the activation of the mitochondria-dependent apoptosis pathway and tubular apoptosis. Apoptosis inhibitors alleviated the activation of the mitochondria-dependent apoptosis pathway. Mechanistically, as a protein phosphatase, PGAM5 could dephosphorylate Bax and facilitate Bax translocation to the mitochondrial membrane. The translocation of Bax to mitochondria increased membrane permeability, decreased mitochondrial membrane potential and facilitated the release of mitochondrial cytochrome c (Cyt c) into the cytoplasm. Knockdown of Bax attenuated PGAM5 overexpression-induced Cyt c release and tubular cell apoptosis. Our results demonstrated that the increase in PGAM5-mediated Bax dephosphorylation and mitochondrial translocation was implicated in the development of AKI by initiating mitochondrial Cyt c release and activating the mitochondria-dependent apoptosis pathway. Targeting this axis might be beneficial for alleviating AKI.


Assuntos
Injúria Renal Aguda , Citocromos c , Camundongos , Animais , Citocromos c/metabolismo , Fosfoglicerato Mutase/metabolismo , Proteína X Associada a bcl-2/metabolismo , Apoptose/fisiologia , Mitocôndrias/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Proteínas de Transporte/metabolismo , Fosfoproteínas Fosfatases/metabolismo
13.
Eur J Med Res ; 28(1): 555, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042816

RESUMO

BACKGROUND: Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common chronic liver disease in China. Our study aimed to evaluate the screening value of the fatty liver index (FLI), hepatic steatosis index (HSI), lipid accumulation product (LAP), visceral adiposity index (VAI), and Zhejiang University index (ZJU), as well as other single indicators for MAFLD. We aimed to find the optimal screening tool and its appropriate cut-off values for rural Uyghur adults. METHODS: We completed a survey of 14,321 Uyghur adults in 51 groups in Kashgar, Xinjiang, in 2016 using a typical sampling method, with 12,794 patients ultimately included in statistical analyses. Fatty liver was diagnosed using ultrasonography. RESULTS: The prevalence of fatty liver disease (FLD) and MAFLD was 16.73% and 16.55%, respectively, and the FLI, HSI, LAP, VAI, and ZJU were all independently associated with an increased risk of MAFLD. The areas under the receiver operating characteristic curves (AUCs) of the FLI for diagnosing MAFLD in men and women were 0.853 and 0.847, respectively. The AUCs of the body mass index (BMI) for diagnosing MAFLD in men and women were 0.850 and 0.852, respectively. Compared with other metabolic-related markers, FLI had the largest AUC. In men, the optimal cut-off values of FLI and BMI for diagnosing MAFLD were 45 (sensitivity 84.83%, specificity 69.57%) and 27.4 (sensitivity 78.47%, specificity 76.30%), respectively. In women, the optimal cut-off values of FLI and BMI for diagnosing MAFLD were 45 (sensitivity 80.11%, specificity 74.23%) and 28.0 (sensitivity 79.56%, specificity 75.41%), respectively. In men and women, an FLI score of < 30 ruled out MAFLD, while a score of ≥ 50 was a basis for diagnosis. CONCLUSION: FLI and BMI had good screening ability for MAFLD and were superior to HSI, LAP, VAI, and ZJU in both sexes.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Masculino , Humanos , Feminino , Estudos Transversais , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Curva ROC , China/epidemiologia
14.
Small ; : e2309007, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037488

RESUMO

Ambient electrocatalytic nitrogen (N2 ) reduction has gained significant recognition as a potential substitute for producing ammonia (NH3 ). However, N2 adsorption and *NN protonation for N2 activation reaction with the competing hydrogen evolution reaction remain a daunting challenge. Herein, a defect-rich TiO2 nanosheet electrocatalyst with PdCu alloy nanoparticles (PdCu/TiO2-x ) is designed to elucidate the reactivity and selectivity trends of N2 cleavage path for N2 -to-NH3 catalytic conversion. The introduction of oxygen vacancy (OV) not only acts as active sites but also effectively promotes the electron transfer from Pd-Cu sites to high-concentration Ti3+ sites, and thus lends to the N2 activation via electron donation of PdCu. OVs-mediated control effectively lowers the reaction barrier of *N2 H and *H adsorption and facilitates the first hydrogenation process of N2 activation. Consequently, PdCu/TiO2-x catalyst attains a high rate of NH3 evolution, reaching 5.0 mmol gcat. -1  h-1 . This work paves a pathway of defect-engineering metal-supported electrocatalysts for high-efficient ammonia electrosynthesis.

15.
J Nat Prod ; 86(12): 2651-2660, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-37967166

RESUMO

Glioma is a clinically heterogeneous type of brain tumor with a poor prognosis. Current treatment approaches have limited effectiveness in treating glioma, highlighting the need for novel drugs. One approach is to explore marine natural products for their therapeutic potential. In this study, we isolated nine shikimate-derived diisoprenyl-cyclohexene/ane-type meroterpenoids (1-9), including four new ones, amphicordins A-D (1-4) from the ascidian-derived fungus Amphichorda felina SYSU-MS7908, and further semisynthesized four derivatives (10-13). Their structures were extensively characterized using 1D and 2D NMR, modified Mosher's method, HR-ESIMS, NMR and ECD calculations, and X-ray crystallography. Notably, amphicordin C (3) possesses a unique benzo[g]chromene (6/6/6) skeleton in this meroterpenoid family. In an anti-glioma assay, oxirapentyn A (7) effectively inhibited the proliferation, migration, and invasion of glioma cells and induced their apoptosis. Furthermore, an in silico analysis suggested that oxirapentyn A has the potential to penetrate the blood-brain barrier. These findings highlight the potential of oxirapentyn A as a candidate for the development of novel anti-glioma drugs.


Assuntos
Beauveria , Glioma , Urocordados , Animais , Humanos , Ácido Chiquímico , Glioma/tratamento farmacológico , Estrutura Molecular
16.
Artigo em Inglês | MEDLINE | ID: mdl-37922330

RESUMO

Photoelectrochemical (PEC) water splitting is a potential solution for a low-carbon society and clean energy storage due to its ability to produce hydrogen and oxygen. However, the slow oxidation half-reaction of the process has limited its overall efficacy, necessitating the development of an efficient photoanode. Colloidal CsPbBr3 nanocrystals (NCs) have been identified as promising candidates due to their high light absorption and valence band position. However, the presence of the electrical insulator, long-chain oleate molecules, on the surface of the CsPbBr3 NCs has hindered efficient charge carrier separation and transport. To solve this problem, short-chain 1,2-ethanedithiol (EDT) ligands were used to replace the oleate ligands on the surface of the CsPbBr3 NCs through a solid-state ligand exchange method. This resulted in a reduction of the nanocrystal spacing and a cross-linking reaction, which improved the photogenerated carrier separation and transport while still passivating the dangling bonds on the CsPbBr3 NC surface. Ultimately, this led to a remarkable photocurrent density of 3.34 mA cm-2 (1.23 VRHE), which was 5.2 times higher than that of the pristine oleate-CsPbBr3 NC (0.64 mA cm-2)-based device. This work presents an efficient way of developing inorganic lead halide perovskite colloidal nanocrystal-based photoanodes through surface ligand engineering.

17.
Nano Lett ; 23(22): 10171-10178, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37922456

RESUMO

Multiplexed quantification of low-abundance protein biomarkers in complex biofluids is important for biomedical research and clinical diagnostics. However, in situ sampling without perturbing biological systems remains challenging. In this work, we report a buoyant biosensor that enables in situ monitoring of protein analytes at attomolar concentrations with a 15 min temporal resolution. The buoyant biosensor implemented with fluorescent nanolabels enabled the ultrasensitive and multiplexed detection and quantification of cytokines. Implementing the biosensor in a digital manner (i.e., counting the individual nanolabels) further improves the low detection limit. We demonstrate that the biosensor enables the detection and quantification of the time-varying concentrations of cytokines (e.g., IL-6 and TNF-α) in macrophage culture media without perturbing the live cells. The easy-to-apply biosensor with attomolar sensitivity and multiplexing capability can enable an in situ analysis of protein biomarkers in various biofluids and tissues to aid in understanding biological processes and diagnosing and treating diverse diseases.


Assuntos
Técnicas Biossensoriais , Citocinas , Biomarcadores
18.
Anal Chem ; 95(48): 17834-17842, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37988125

RESUMO

Precise and sensitive analysis of exosomal microRNA (miRNA) is of great importance for noninvasive early disease diagnosis, but it remains a great challenge to detect exosomal miRNA in human blood samples because of their small size, high sequence homology, and low abundance. Herein, we integrated reliable Pt-S bond-mediated three-dimensional (3D) DNA nanomachine and magnetic separation in a homogeneous electrochemical strategy for the detection of exosomal miRNA with low background and high sensitivity. The 3D DNA nanomachine was easily prepared via a facile and rapid freezing method, and it was capable of resisting the influence of biothiols, thus endowing it with high stability. Notably, the as-developed magnetic 3D DNA nanomachine not only enabled the detection system to have a low background but also coupled with liposome nanocarriers to synergistically amplify the current signal. Consequently, by ingeniously combining the low background and multiple signal-amplification strategies in homogeneous electrochemical biosensing, highly sensitive detection of exosomal miRNA was successfully achieved. More significantly, with good anti-interference ability, the as-proposed method could effectively discriminate plasma samples from cancer patients and healthy subjects, thus showing a high potential for application in the nondestructive early clinical diagnosis of disease.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Humanos , MicroRNAs/análise , DNA/análise , Lipossomos , Fenômenos Físicos , Fenômenos Magnéticos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
19.
Biomed Opt Express ; 14(9): 4775-4789, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37791263

RESUMO

Cutaneous inflammation is an acute skin disease characterized by edema and vascular hyperplasia. Longitudinal monitoring of vasculature is crucial for studying the development of inflammation and evaluating the therapeutic efficacy of drugs. Optical-resolution photoacoustic microscopy (OR-PAM) is a hybrid imaging tool for non-invasive and label-free visualization of microcirculations with a capillary-scale spatial resolution. In this study, we assess the feasibility of OR-PAM for long-term monitoring of vascular changes in 12-O-Tetradecanoylphorbol-13-Acetate (TPA)-induced mouse models, as well as the corresponding treatment process. Quantitative vascular evaluation is conducted based on derived key parameters, including vessel length, branchpoint number, vessel area fraction, vessel diameter, fractal dimension, vessel tortuosity and ear thickness, which reveal that vascular morphological changes are highly dependent on the concentration of TPA and existence of therapeutic drugs. Furthermore, the results show the potential of OR-PAM in the clinical management of inflammation and as an effective tool to evaluate vascular responses to pharmacological interventions in vivo.

20.
Molecules ; 28(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836792

RESUMO

Fabricating heterostructures with abundant interfaces and delicate nanoarchitectures is an attractive approach for optimizing photocatalysts. Herein, we report the facile synthesis of BiOCl nanoflake/FeOCl nanospindle heterostructures through a solution chemistry method at room temperature. Characterizations, including XRD, SEM, TEM, EDS, and XPS, were employed to investigate the synthesized materials. The results demonstrate that the in situ reaction between the Bi precursors and the surface Cl- of FeOCl enabled the bounded nucleation and growth of BiOCl on the surface of FeOCl nanospindles. Stable interfacial structures were established between BiOCl nanoflakes and FeOCl nanospindles using Cl- as the bridge. Regulating the Bi-to-Fe ratios allowed for the optimization of the BiOCl/FeOCl interface, thereby facilitating the separation of photogenerated carriers and accelerating the photocatalytic degradation of RhB. The BiOCl/FeOCl heterostructures with an optimal composition of 15% BiOCl exhibited ~90 times higher visible-light photocatalytic activity than FeOCl. Based on an analysis of the band structures and reactive oxygen species, we propose an S-scheme mechanism to elucidate the significantly enhanced photocatalytic performance observed in the BiOCl/FeOCl heterostructures.

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