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1.
Nature ; 620(7976): 994-1000, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37290482

RESUMEN

All-perovskite tandem solar cells promise higher power-conversion efficiency (PCE) than single-junction perovskite solar cells (PSCs) while maintaining a low fabrication cost1-3. However, their performance is still largely constrained by the subpar performance of mixed lead-tin (Pb-Sn) narrow-bandgap (NBG) perovskite subcells, mainly because of a high trap density on the perovskite film surface4-6. Although heterojunctions with intermixed 2D/3D perovskites could reduce surface recombination, this common strategy induces transport losses and thereby limits device fill factors (FFs)7-9. Here we develop an immiscible 3D/3D bilayer perovskite heterojunction (PHJ) with type II band structure at the Pb-Sn perovskite-electron-transport layer (ETL) interface to suppress the interfacial non-radiative recombination and facilitate charge extraction. The bilayer PHJ is formed by depositing a layer of lead-halide wide-bandgap (WBG) perovskite on top of the mixed Pb-Sn NBG perovskite through a hybrid evaporation-solution-processing method. This heterostructure allows us to increase the PCE of Pb-Sn PSCs having a 1.2-µm-thick absorber to 23.8%, together with a high open-circuit voltage (Voc) of 0.873 V and a high FF of 82.6%. We thereby demonstrate a record-high PCE of 28.5% (certified 28.0%) in all-perovskite tandem solar cells. The encapsulated tandem devices retain more than 90% of their initial performance after 600 h of continuous operation under simulated one-sun illumination.

2.
Nature ; 603(7899): 73-78, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35038717

RESUMEN

All-perovskite tandem solar cells hold the promise of surpassing the efficiency limits of single-junction solar cells1-3; however, until now, the best-performing all-perovskite tandem solar cells have exhibited lower certified efficiency than have single-junction perovskite solar cells4,5. A thick mixed Pb-Sn narrow-bandgap subcell is needed to achieve high photocurrent density in tandem solar cells6, yet this is challenging owing to the short carrier diffusion length within Pb-Sn perovskites. Here we develop ammonium-cation-passivated Pb-Sn perovskites with long diffusion lengths, enabling subcells that have an absorber thickness of approximately 1.2 µm. Molecular dynamics simulations indicate that widely used phenethylammonium cations are only partially adsorbed on the surface defective sites at perovskite crystallization temperatures. The passivator adsorption is predicted to be enhanced using 4-trifluoromethyl-phenylammonium (CF3-PA), which exhibits a stronger perovskite surface-passivator interaction than does phenethylammonium. By adding a small amount of CF3-PA into the precursor solution, we increase the carrier diffusion length within Pb-Sn perovskites twofold, to over 5 µm, and increase the efficiency of Pb-Sn perovskite solar cells to over 22%. We report a certified efficiency of 26.4% in all-perovskite tandem solar cells, which exceeds that of the best-performing single-junction perovskite solar cells. Encapsulated tandem devices retain more than 90% of their initial performance after 600 h of operation at the maximum power point under 1 Sun illumination in ambient conditions.

3.
J Infect Dis ; 229(5): 1306-1316, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38243412

RESUMEN

BACKGROUND: Human immunodeficiency virus 1 (HIV-1) tissue reservoirs remain the main obstacle against an HIV cure. Limited information exists regarding cannabis's effects on HIV-1 infections in vivo, and the impact of cannabis use on HIV-1 parenchymal tissue reservoirs is unexplored. METHODS: To investigate whether cannabis use alters HIV-1 tissue reservoirs, we systematically collected 21 postmortem brain and peripheral tissues from 20 men with subtype C HIV-1 and with suppressed viral load enrolled in Zambia, 10 of whom tested positive for cannabis use. The tissue distribution and copies of subtype C HIV-1 LTR, gag, env DNA and RNA, and the relative mRNA levels of cytokines IL-1ß, IL-6, IL-10, and TGF-ß1 were quantified using PCR-based approaches. Utilizing generalized linear mixed models we compared persons with HIV-1 and suppressed viral load, with and without cannabis use. RESULTS: The odds of tissues harboring HIV-1 DNA and the viral DNA copies in those tissues were significantly lower in persons using cannabis. Moreover, the transcription levels of proinflammatory cytokines IL-1ß and IL-6 in lymphoid tissues of persons using cannabis were also significantly lower. CONCLUSIONS: Our findings suggested that cannabis use is associated with reduced sizes and inflammatory cytokine expression of subtype C HIV-1 reservoirs in men with suppressed viral load.


Asunto(s)
Citocinas , Infecciones por VIH , VIH-1 , Carga Viral , Humanos , Masculino , VIH-1/genética , VIH-1/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Adulto , Citocinas/metabolismo , Citocinas/genética , Provirus/genética , Persona de Mediana Edad , Zambia , ADN Viral , Antirretrovirales/uso terapéutico , Encéfalo/virología , Encéfalo/metabolismo , Adulto Joven , Uso de la Marihuana/metabolismo
4.
Small ; 20(23): e2307603, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38213024

RESUMEN

Bacterial cellulose/oxidized bacterial cellulose nanofibrils (BC/oxBCNFs) macro-fibers are developed as a novel scaffold for vascular tissue engineering. Utilizing a low-speed rotary coagulation spinning technique and precise solvent control, macro-fibers with a unique heterogeneous structure with dense surface and porous core are created. Enhanced by a polydopamine (PDA) coating, these macro-fibers offer robust mechanical integrity, high biocompatibility, and excellent cell adhesion. When cultured with endothelial cells (ECs) and smooth muscle cells (SMCs), the macro-fibers support healthy cell proliferation and exhibit a unique spiral SMC alignment, demonstrating their vascular suitability. This innovative strategy opens new avenues for advances in tissue engineering.


Asunto(s)
Celulosa , Nanofibras , Ingeniería de Tejidos , Andamios del Tejido , Ingeniería de Tejidos/métodos , Nanofibras/química , Andamios del Tejido/química , Celulosa/química , Humanos , Miocitos del Músculo Liso/citología , Proliferación Celular/efectos de los fármacos , Adhesión Celular , Células Endoteliales/citología , Células Endoteliales de la Vena Umbilical Humana , Indoles/química , Polímeros
5.
J Neurovirol ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943022

RESUMEN

Although previous studies have suggested that subtype B HIV-1 proviruses in the brain are associated with physiological changes and immune activation accompanied with microgliosis and astrogliosis, and indicated that both HIV-1 subtype variation and geographical location might influence the neuropathogenicity of HIV-1 in the brain. The natural course of neuropathogenesis of the most widespread subtype C HIV-1 has not been adequately investigated, especially for people living with HIV (PLWH) in sub-Saharan Africa. To characterize the natural neuropathology of subtype C HIV-1, postmortem frontal lobe and basal ganglia tissues were collected from nine ART-naïve individuals who died of late-stage AIDS with subtype C HIV-1 infection, and eight uninfected deceased individuals as controls. Histological staining was performed on all brain tissues to assess brain pathologies. Immunohistochemistry (IHC) against CD4, p24, Iba-1, GFAP, and CD8 in all brain tissues was conducted to evaluate potential viral production and immune activation. Histological results showed mild perivascular cuffs of lymphocytes only in a minority of the infected individuals. Viral capsid p24 protein was only detected in circulating immune cells of one infected individual, suggesting a lack of productive HIV-1 infection of the brain even at the late-stage of AIDS. Notably, similar levels of Iba-1 or GFAP between HIV + and HIV- brain tissues indicated a lack of microgliosis and astrogliosis, respectively. Similar levels of CD8 + cytotoxic T lymphocyte (CTL) infiltration between HIV + and HIV- brain tissues indicated CTL were not likely to be involved within subtype C HIV-1 infected participants of this cohort. Results from this subtype C HIV-1 study suggest that there is a lack of productive infection and limited neuropathogenesis by subtype C HIV-1 even at late-stage disease, which is in contrast to what was reported for subtype B HIV-1 by other investigators.

6.
Pharmacol Res ; 205: 107235, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38815879

RESUMEN

Diabetic cardiomyopathy (DCM) is a major complication of diabetes and is characterized by left ventricular dysfunction. Currently, there is a lack of effective treatments for DCM. Ubiquitin-specific protease 7 (USP7) plays a key role in various diseases. However, whether USP7 is involved in DCM has not been established. In this study, we demonstrated that USP7 was upregulated in diabetic mouse hearts and NMCMs co-treated with HG+PA or H9c2 cells treated with PA. Abnormalities in diabetic heart morphology and function were reversed by USP7 silencing through conditional gene knockout or chemical inhibition. Proteomic analysis coupled with biochemical validation confirmed that PCG1ß was one of the direct protein substrates of USP7 and aggravated myocardial damage through coactivation of the PPARα signaling pathway. USP7 silencing restored the expression of fatty acid metabolism-related proteins and restored mitochondrial homeostasis by inhibiting mitochondrial fission and promoting fusion events. Similar effects were also observed in vitro. Our data demonstrated that USP7 promoted cardiometabolic metabolism disorders and mitochondrial homeostasis dysfunction via stabilizing PCG1ß and suggested that silencing USP7 may be a therapeutic strategy for DCM.


Asunto(s)
Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Homeostasis , Ratones Endogámicos C57BL , Peptidasa Específica de Ubiquitina 7 , Animales , Peptidasa Específica de Ubiquitina 7/metabolismo , Peptidasa Específica de Ubiquitina 7/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/genética , Masculino , Ratones , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Mitocondrias Cardíacas/metabolismo , Línea Celular , Ratones Noqueados , Ratas , Mitocondrias/metabolismo , Humanos
7.
Eur Radiol ; 34(1): 60-68, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37566265

RESUMEN

OBJECTIVES: To investigate measurements derived from plain and enhanced spectral CT in differentiating osteoblastic bone metastasis (OBM) from bone island (BI). MATERIALS AND METHODS: From January to November 2020, 73 newly diagnosed cancer patients with 201 bone lesions (OBM = 92, BI = 109) having received spectral CT were retrospectively enrolled. Measurements including CT values of 40-140 keV, slope of the spectral curve, effective atomic number (Zeff), water (calcium) density, calcium (water) density, and Iodine (calcium) density were derived from manually segmented lesions on plain and enhanced spectral CT, and then analyzed using Student t-test and Pearson's correlation. Multivariate analysis was performed to build models (plain spectral model, enhanced spectral CT model, and combined model) for the discrimination of OBM and BI with performance evaluated using receiver operator characteristics curve and DeLong test. RESULTS: All features were significantly different between the BI group and OBM group (all p < 0.05), highly correlated with the corresponding features between plain and enhanced spectral CT both in OBM (r: 0.392-0.763) and BI (r: 0.430-0.544). As for the model performance, the combined model achieved the best performance (AUC = 0.925, 95% CI: 0.879 to 0.957), which significantly outperformed the plain spectral CT model (AUC = 0.815, 95% CI: 0.754 to 0.866, p < 0.001) and enhanced spectral CT model (AUC = 0.901, 95% CI: 0.852 to 0.939, p = 0.024) in differentiating OBM and BI. CONCLUSION: In addition to plain spectral CT measurements, enhanced spectral CT measurements would further significantly benefit the differential diagnosis. CLINICAL RELEVANCE STATEMENT: Measurements derived either from plain or enhanced spectral CT could provide additional valuable information to improve the differential diagnosis between OBM and BI in newly diagnosed cancer patients. KEY POINTS: • We intend to investigate plain and enhanced spectral CT measurements in differentiating OBM from BI. • Both plain and enhanced spectral CT help in discriminating OBM and BI in newly diagnosed cancer patients. • Enhanced spectral CT measurements further improve plain spectral CT measurements-based differential diagnosis.


Asunto(s)
Neoplasias Óseas , Calcio , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Neoplasias Óseas/diagnóstico por imagen , Agua
8.
Eur Radiol ; 34(1): 182-192, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37566270

RESUMEN

OBJECTIVES: To propose a novel model-free data-driven approach based on the voxel-wise mapping of DCE-MRI time-intensity-curve (TIC) profiles for quantifying and visualizing hemodynamic heterogeneity and to validate its potential clinical applications. MATERIALS AND METHODS: From December 2018 to July 2022, 259 patients with 325 pathologically confirmed breast lesions who underwent breast DCE-MRI were retrospectively enrolled. Based on the manually segmented breast lesions, the TIC of each voxel within the 3D whole lesion was classified into 19 subtypes based on wash-in rate (nonenhanced, slow, medium, and fast), wash-out enhancement (persistent, plateau, and decline), and wash-out stability (steady and unsteady), and the composition ratio of these 19 subtypes for each lesion was calculated as a new feature set (type-19). The three-type TIC classification, semiquantitative parameters, and type-19 features were used to build machine learning models for identifying lesion malignancy and classifying histologic grades, proliferation status, and molecular subtypes. RESULTS: The type-19 feature-based model significantly outperformed models based on the three-type TIC method and semiquantitative parameters both in distinguishing lesion malignancy (respectively; AUC = 0.875 vs. 0.831, p = 0.01 and 0.875vs. 0.804, p = 0.03), predicting tumor proliferation status (AUC = 0.890 vs. 0.548, p = 0.006 and 0.890 vs. 0.596, p = 0.020), but not in predicting histologic grades (p = 0.820 and 0.970). CONCLUSION: In addition to conventional methods, the proposed computational approach provides a novel, model-free, data-driven approach to quantify and visualize hemodynamic heterogeneity. CLINICAL RELEVANCE STATEMENT: Voxel-wise intra-lesion mapping of TIC profiles allows for visualization of hemodynamic heterogeneity and its composition ratio for differentiation of malignant and benign breast lesions. KEY POINTS: • Voxel-wise TIC profiles were mapped, and their composition ratio was compared between various breast lesions. • The model based on the composition ratio of voxel-wise TIC profiles significantly outperformed the three-type TIC classification model and the semiquantitative parameters model in lesion malignancy differentiation and tumor proliferation status prediction in breast lesions. • This novel, data-driven approach allows the intuitive visualization and quantification of the hemodynamic heterogeneity of breast lesions.


Asunto(s)
Neoplasias de la Mama , Neoplasias , Humanos , Femenino , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Mama/diagnóstico por imagen , Mama/patología , Tiempo , Neoplasias/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Medios de Contraste
9.
Eur Radiol ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38252276

RESUMEN

OBJECTIVE: We aimed to evaluate the mitral valve calcification and mitral structure detected by cardiac computed tomography (cardiac CT) and establish a scoring model based on cardiac CT and clinical factors to predict early good mitral valve repair (EGMR) and guide surgical strategy in rheumatic mitral disease (RMD). MATERIALS AND METHODS: This is a retrospective bi-center cohort study. Based on cardiac CT, mitral valve calcification and mitral structure in RMD were quantified and evaluated. The primary outcome was EGMR. A logical regression algorithm was applied to the scoring model. RESULTS: A total of 579 patients were enrolled in our study from January 1, 2019, to August 31, 2022. Of these, 443 had baseline cardiac CT scans of adequate quality. The calcification quality score, calcification and thinnest part of the anterior leaflet clean zone, and papillary muscle symmetry were the independent CT factors of EGMR. Coronary artery disease and pulmonary artery pressure were the independent clinical factors of EGMR. Based on the above six factors, a scoring model was established. Sensitivity = 95% and specificity = 95% were presented with a cutoff value of 0.85 and 0.30 respectively. The area under the receiver operating characteristic of external validation set was 0.84 (95% confidence interval [CI] 0.73-0.93). CONCLUSIONS: Mitral valve repair is recommended when the scoring model value > 0.85 and mitral valve replacement is prior when the scoring model value < 0.30. This model could assist in guiding surgical strategies for RMD. CLINICAL RELEVANCE STATEMENT: The model established in this study can serve as a reference indicator for surgical repair in rheumatic mitral valve disease. KEY POINTS: • Cardiac CT can reflect the mitral structure in detail, especially for valve calcification. • A model based on cardiac CT and clinical factors for predicting early good mitral valve repair was established. • The developed model can help cardiac surgeons formulate appropriate surgical strategies.

10.
Br J Clin Pharmacol ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845212

RESUMEN

AIMS: Although there are various model-based approaches to individualized vancomycin (VCM) administration, few have been reported for adult patients with periprosthetic joint infection (PJI). This work attempted to develop a machine learning (ML)-based model for predicting VCM trough concentration in adult PJI patients. METHODS: The dataset of 287 VCM trough concentrations from 130 adult PJI patients was split into a training set (229) and a testing set (58) at a ratio of 8:2, and an independent external 32 concentrations were collected as a validation set. A total of 13 covariates and the target variable (VCM trough concentration) were included in the dataset. A covariate model was respectively constructed by support vector regression, random forest regression and gradient boosted regression trees and interpreted by SHapley Additive exPlanation (SHAP). RESULTS: The SHAP plots visualized the weight of the covariates in the models, with estimated glomerular filtration rate and VCM daily dose as the 2 most important factors, which were adopted for the model construction. Random forest regression was the optimal ML algorithm with a relative accuracy of 82.8% and absolute accuracy of 67.2% (R2 =.61, mean absolute error = 2.4, mean square error = 10.1), and its prediction performance was verified in the validation set. CONCLUSION: The proposed ML-based model can satisfactorily predict the VCM trough concentration in adult PJI patients. Its construction can be facilitated with only 2 clinical parameters (estimated glomerular filtration rate and VCM daily dose), and prediction accuracy can be rationalized by SHAP values, which highlights a profound practical value for clinical dosing guidance and timely treatment.

11.
Analyst ; 149(5): 1447-1454, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38197456

RESUMEN

Ventilator-associated pneumonia (VAP) is a prevalent disease caused by microbial infection, resulting in significant morbidity and mortality within the intensive care unit (ICU). The rapid and accurate identification of pathogenic bacteria causing VAP can assist clinicians in formulating timely treatment plans. In this study, we attempted to differentiate bacterial species in VAP by utilizing the volatile organic compounds (VOCs) released by pathogens. We cultured 6 common bacteria in VAP in vitro, including Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Staphylococcus aureus, which covered most cases of VAP infection in clinic. After the VOCs released by bacteria were collected in sampling bags, they were quantitatively detected by a proton transfer reaction-mass spectrometry (PTR-MS), and the characteristic ions were qualitatively analyzed through a fast gas chromatography-proton transfer reaction-mass spectrometry (FGC-PTR-MS). After conducting principal component analysis (PCA) and analysis of similarities (ANOSIM), we discovered that the VOCs released by 6 bacteria exhibited differentiation following 3 h of quantitative cultivation in vitro. Additionally, we further investigated the variations in the types and concentrations of bacterial VOCs. The results showed that by utilizing the differences in types of VOCs, 6 bacteria could be classified into 5 sets, except for A. baumannii and E. cloacae which were indistinguishable. Furthermore, we observed significant variations in the concentration ratio of acetaldehyde and methyl mercaptan released by A. baumannii and E. cloacae. In conclusion, the VOCs released by bacteria could effectively differentiate the 6 pathogens commonly associated with VAP, which was expected to assist doctors in formulating treatment plans in time and improve the survival rate of patients.


Asunto(s)
Neumonía Asociada al Ventilador , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Protones , Neumonía Asociada al Ventilador/diagnóstico , Neumonía Asociada al Ventilador/microbiología , Espectrometría de Masas/métodos , Bacterias
12.
Artículo en Inglés | MEDLINE | ID: mdl-38289452

RESUMEN

Myocardial ischemia reperfusion injury (MIRI) represents a prevalent and severe cardiovascular condition that arises primarily after myocardial infarction recanalization, cardiopulmonary bypass surgery, and both stable and unstable angina pectoris. MIRI can induce malignant arrhythmias and heart failure, thereby increasing the morbidity and mortality rates associated with cardiovascular diseases. Hence, it is important to assess the potential pathological mechanisms of MIRI and develop effective treatments. The role of circular RNAs (circRNAs) in MIRI has increasingly become a topic of interest in recent years. Moreover, significant evidence suggests that circRNAs play a critical role in MIRI pathogenesis, thereby representing a promising therapeutic target. This review aimed to provide a comprehensive overview of the current understanding of the role of circRNAs in MIRI and discuss the mechanisms through which circRNAs contribute to MIRI development and progression, including their effects on apoptosis, inflammation, oxidative stress, and autophagy. Furthermore, the potential therapeutic applications of circRNAs in MIRI treatment, including the use of circRNA-based therapies and modulation of circRNA expression levels, have been explored. Overall, this paper highlights the importance of circRNAs in MIRI and underscores their potential as novel therapeutic targets.

13.
Acta Pharmacol Sin ; 45(5): 988-1001, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38279043

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disease that is substantially associated with obesity-induced chronic inflammation. Macrophage activation and macrophage-medicated inflammation play crucial roles in the development and progression of NAFLD. Furthermore, fibroblast growth factor receptor 1 (FGFR1) has been shown to be essentially involved in macrophage activation. This study investigated the role of FGFR1 in the NAFLD pathogenesis and indicated that a high-fat diet (HFD) increased p-FGFR1 levels in the mouse liver, which is associated with increased macrophage infiltration. In addition, macrophage-specific FGFR1 knockout or administration of FGFR1 inhibitor markedly protected the liver from HFD-induced lipid accumulation, fibrosis, and inflammatory responses. The mechanistic study showed that macrophage-specific FGFR1 knockout alleviated HFD-induced liver inflammation by suppressing the activation of MAPKs and TNF signaling pathways and reduced fat deposition in hepatocytes, thereby inhibiting the activation of hepatic stellate cells. In conclusion, the results of this research revealed that FGFR1 could protect the liver of HFD-fed mice by inhibiting MAPKs/TNF-mediated inflammatory responses in macrophages. Therefore, FGFR1 can be employed as a target to prevent the development and progression of NAFLD.


Asunto(s)
Dieta Alta en Grasa , Macrófagos , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Factor de Necrosis Tumoral alfa , Animales , Dieta Alta en Grasa/efectos adversos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Masculino , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/etiología , Factor de Necrosis Tumoral alfa/metabolismo , Ratones Noqueados , Hígado/patología , Hígado/metabolismo , Transducción de Señal , Inflamación/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos
14.
Anal Chem ; 95(39): 14592-14599, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37683102

RESUMEN

Due to the comparable stability between the perfect-base pair and the wobble-base pair, a precise differentiation of the wobble-type allele has remained a challenge, often leading to false results. Herein, we proposed a ligase chain reaction (LCR)-based ratiometric electrochemical DNA sensor, namely, R-eLCR, for a precise typing of the wobble-type allele, in which the traditionally recognized "negative" signal of wobble-base pair-mediated amplification was fully utilized as a "positive" one and a ratiometric readout mode was employed to ameliorated the underlying potential external influence and improved its detection accuracy in the typing of the wobble-type allele. The results showed that the ratio between current of methylene blue (IMB) and current of ferrocene (IFc) was partitioned in three regions and three types of wobble-type allele were thus precisely differentiated (AA homozygote: IMB/IFc > 2; GG homozygote: IMB/IFc < 1; GA heterozygote: 1 < IMB/IFc < 2); the proposed R-eLCR successfully discriminated the three types of CYP2C19*2 allele in nine cases of human whole blood samples, which was consistent with those of the sequencing method. These results evidence that the proposed R-eLCR can serve as an accurate and robust alternative for the identification of wobble-type allele, which lays a solid foundation and holds great potential for precision medicine.


Asunto(s)
Técnicas Biosensibles , Reacción en Cadena de la Ligasa , Humanos , Alelos , Genotipo , Citocromo P-450 CYP2C19 , Técnicas Electroquímicas , Oro , Límite de Detección
15.
Anal Chem ; 95(12): 5331-5339, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36926822

RESUMEN

As an enzyme-free exponential nucleic acid amplification method, the click chemistry-mediated ligation chain reaction (ccLCR) has shown great prospects in the molecular diagnosis. However, the current optics-based ccLCR is challenged by remarkable nonspecific amplification, severely hindering its future application. This study demonstrated that the severe nonspecific amplification was generated probably due to high random collision in the high DNA probe concentration (µM level). To solve this hurdle, a nucleic acid template-dominated ccLCR was constructed using nM-level DNA probes and read on an electrochemical platform (cc-eLCR). Under the optimal conditions, the proposed cc-eLCR detected a low-level nucleic acid target (1 fM) with a single-base resolution. Furthermore, this assay was applied to detect the target of interest in cell extracts with a satisfactory result. The proposed cc-eLCR offers huge possibility for click chemistry-mediated enzyme-free exponential nucleic acid amplification in the application of medical diagnosis and biomedical research.


Asunto(s)
Técnicas Biosensibles , ARN , Química Clic/métodos , Técnicas Biosensibles/métodos , ADN/química , Sondas de ADN/genética , Sondas de ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , Hibridación de Ácido Nucleico
16.
Small ; 19(33): e2300964, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37066740

RESUMEN

The long-range magnetic ordering in frustrated magnetic systems is stabilized by coupling magnetic moments to various degrees of freedom, for example, by enhancing magnetic anisotropy via lattice distortion. Here, the unconventional spin-lattice coupled metamagnetic properties of atomically-thin CrOCl, a van der Waals antiferromagnet with inherent magnetic frustration rooted in the staggered square lattice, are reported. Using temperature- and angle-dependent tunneling magnetoconductance (TMC), in complementary with magnetic torque and first-principles calculations, the antiferromagnetic (AFM)-to-ferrimagnetic (FiM) metamagnetic transitions (MTs) of few-layer CrOCl are revealed to be triggered by collective magnetic moment flipping rather than the established spin-flop mechanism, when external magnetic field (H) enforces a lattice reconstruction interlocked with the five-fold periodicity of the FiM phase. The spin-lattice coupled MTs are manifested by drastic jumps in TMC, which show anomalous upshifts at the transition thresholds and persist much higher above the AFM Néel temperature. While the MTs exhibit distinctive triaxial anisotropy, reflecting divergent magnetocrystalline anisotropy of the c-axis AFM ground state, the resulting FiM phase has an a-c easy plane in which the magnetization axis is freely rotated by H. At the 2D limit, such a field-tunable FiM phase may provide unique opportunities to explore exotic emergent phenomena and novel spintronics devices.

17.
J Transl Med ; 21(1): 470, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37454080

RESUMEN

BACKGROUND: The tumor-adipose microenvironment (TAME) is characterized by the enrichment of adipocytes, and is considered a special ecosystem that supports cancer progression. However, the heterogeneity and diversity of adipocytes in TAME remains poorly understood. METHODS: We conducted a single-cell RNA sequencing analysis of adipocytes in mouse and human white adipose tissue (WAT). We analyzed several adipocyte subtypes to evaluate their relationship and potential as prognostic factors for overall survival (OS). The potential drugs are screened by using bioinformatics methods. The tumor-promoting effects of a typical adipocyte subtype in breast cancer are validated by performing in vitro functional assays and immunohistochemistry (IHC) in clinical samples. RESULTS: We profiled a comprehensive single-cell atlas of adipocyte in mouse and human WAT and described their characteristics, origins, development, functions and interactions with immune cells. Several cancer-associated adipocyte subtypes, namely DPP4+ adipocytes in visceral adipose and ADIPOQ+ adipocytes in subcutaneous adipose, are identified. We found that high levels of these subtypes are associated with unfavorable outcomes in four typical adipose-associated cancers. Some potential drugs including Trametinib, Selumetinib and Ulixertinib are discovered. Emphatically, knockdown of adiponectin receptor 1 (AdipoR1) and AdipoR2 impaired the proliferation and invasion of breast cancer cells. Patients with AdipoR2-high breast cancer display significantly shorter relapse-free survival (RFS) than those with AdipoR2-low breast cancer. CONCLUSION: Our results provide a novel understanding of TAME at the single-cell level. Based on our findings, several adipocyte subtypes have negative impact on prognosis. These cancer-associated adipocytes may serve as key prognostic predictor and potential targets for treatment in the future.


Asunto(s)
Neoplasias de la Mama , Ecosistema , Humanos , Ratones , Animales , Femenino , Recurrencia Local de Neoplasia , Adipocitos , Neoplasias de la Mama/genética , Tejido Adiposo Blanco , Obesidad , Análisis de la Célula Individual , Tejido Adiposo , Microambiente Tumoral
18.
Cardiovasc Diabetol ; 22(1): 21, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717862

RESUMEN

OBJECTIVE: We aimed to examine the association of triglyceride-glucose index (TyG) with risk for cardiovascular disease (CVD) among postmenopausal women. METHODS: A total of 7741 participants met the inclusion criteria, and were included in the analysis. The TyG index was calculated as ln (triglyceride [mg/dL] × fasting blood glucose [mg/dL]/2). The participants were classified into four groups by the quartiles of TyG index, and the Q1 group was used as the reference group. The cumulative incidence of CVD for the groups were compared using the Kaplan-Meier curves. The association between the TyG index and risk of CVD among postmenopausal women was assessed by the Cox proportional hazards models (hazard ratio [HR], 95% confidence intervals [CI]). RESULTS: During a median follow-up of 12 years, a total of 383 (4.95%) participants developed incident CVD. After adjusting for potential confounding factors, a high baseline TyG index (Q4 group) was associated with higher future risk of CVD, the HR (95% CI) of CVD risk was 1.70 (1.21-2.38) in Q4 group compared with the Q1 group. Subgroup analyses showed the Q4 group was significantly associated with the risk of CVD, regardless of age at menopause (younger than 50 years; 50 years and older) and obesity status. CONCLUSIONS: Higher TyG index at baseline as a marker of insulin resistance (IR), is associated with higher risk of future CVD among postmenopausal women. The TyG index may serve as a simple and easy marker for early identification of high-risk individuals in the postmenopausal women.


Asunto(s)
Enfermedades Cardiovasculares , Glucosa , Humanos , Femenino , Persona de Mediana Edad , Factores de Riesgo , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Triglicéridos , Posmenopausia , Glucemia , Medición de Riesgo , Biomarcadores
19.
J Magn Reson Imaging ; 57(3): 824-833, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35816177

RESUMEN

BACKGROUND: Amide proton transfer (APT) imaging has been increasingly applied in tumor characterization. However, its value in evaluating breast cancer remains undetermined. PURPOSE: To assess the diagnostic performance of APT imaging in breast cancer and its association with prognostic histopathologic characteristics. STUDY TYPE: Prospective. SUBJECTS: Eighty-four patients with breast lesions. FIELD STRENGTH/SEQUENCE: A 3.0 T/single-shot fast spin echo APT imaging. ASSESSMENT: APTw signal in breast lesion was quantified. Lesion malignancy, T stage, grades, Ki-67 index, molecular biomarkers (estrogen receptor [ER] expression, progesterone receptor [PR] expression, human epidermal growth factor receptor [HER-2] expression), molecular subtypes (luminal A, luminal B, triple negative, and HER-2 enriched) were determined. STATISTICAL TESTS: Student t-test, one-way analysis of variance, receiver operating characteristic analysis, and Pearson's correlation with P < 0.05 as statistical significance. RESULTS: APTw signal was significantly higher in malignant lesions (1.55% ± 1.24%) than in benign lesions (0.54% ± 1.13%), and in grade III lesions than in grade II lesions (1.65% ± 0.84% vs. 0.96% ± 0.96%), and in T2- (1.57% ± 0.64%) and T3-stage lesions (1.54% ± 0.63%) than in T1-stage lesions (0.81% ± 0.64%) for invasive breast carcinoma of no special type. APTw signal significantly correlated with Ki-67 index (r = 0.364) but showed no significant difference in groups of ER (P = 0.069), PR (P = 0.069), HER-2 (P = 0.961), and among molecular subtypes (P = 0.073). DATA CONCLUSION: APT imaging shows potential in differentiating breast lesion malignancy and associates with prognosis-related tumor grade, T stage, and proliferative activity. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Neoplasias de la Mama , Protones , Humanos , Femenino , Amidas , Antígeno Ki-67/metabolismo , Estudios Prospectivos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Mama/metabolismo
20.
Amino Acids ; 55(10): 1317-1331, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37670010

RESUMEN

The emergence of drug-resistant superbugs has necessitated a pressing need for innovative antibiotics. Antimicrobial peptides (AMPs) have demonstrated broad-spectrum antibacterial activity, reduced susceptibility to resistance, and immunomodulatory effects, rendering them promising for combating drug-resistant microorganisms. This study employed computational simulation methods to screen and design AMPs specifically targeting ESKAPE pathogens. Particularly, AMPs were rationally designed to target the BamA and obtain novel antimicrobial peptide sequences. The designed AMPs were assessed for their antibacterial activities, mechanisms, and stability. Molecular docking and dynamics simulations demonstrated the interaction of both designed AMPs, 11pep and D-11pep, with the ß1, ß9, ß15, and ß16 chains of BamA, resulting in misfolding of outer membrane proteins and antibacterial effects. Subsequent antibacterial investigations confirmed the broad-spectrum activity of both 11pep and D-11pep, with D-11pep demonstrating higher potency against resistant Gram-negative bacteria. D-11pep exhibited MICs of 16, 8, and 32 µg/mL against carbapenem-resistant Escherichia coli, carbapenem-resistant Pseudomonas aeruginosa, and multi-drug-resistant Acinetobacter baumannii, respectively, with a concomitant lower resistance induction. Mechanism of action studies confirmed that peptides could disrupt the bacterial outer membrane, aligning with the findings of molecular dynamics simulations. Additionally, D-11pep demonstrated superior stability and reduced toxicity in comparison to 11pep. The findings of this study underscore the efficacy of rational AMP design that targets BamA, along with the utilization of D-amino acid replacements as a strategy for developing AMPs against drug-resistant bacteria.


Asunto(s)
Péptidos Catiónicos Antimicrobianos , Péptidos Antimicrobianos , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Simulación del Acoplamiento Molecular , Antibacterianos/química , Carbapenémicos , Pruebas de Sensibilidad Microbiana
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