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1.
Angew Chem Int Ed Engl ; : e202409004, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837495

RESUMEN

Previous N-glycosylation approaches have predominately involved acidic conditions, facing challenges of low stereoselectivity and limited scope. Herein, we introduce a radical activation strategy that enables versatile and stereoselective N-glycosylation using readily accessible glycosyl sulfinate as a donor under basic conditions and exhibits exceptional tolerance towards various N-aglycones containing alkyl, aryl, heteroaryl and nucleobase functionalities. Preliminary mechanistic studies indicate a pivotal role of iodide, which orchestrates the formation of a glycosyl radical from the glycosyl sulfinate and subsequent generation of the key intermediate, a configurationally well-defined glycosyl iodide, which is subsequently attacked by an N-aglycone in a stereospecific SN2 manner to give the desired N-glycosides. An alternative route involving the coupling of a glycosyl radical and a nitrogen-centered radical is also proposed, affording the exclusive 1,2-trans product. This novel approach promises to broaden the synthetic landscape of N-glycosides, offering a powerful tool for the construction of complex glycosidic structures under mild conditions.

2.
Eur Radiol ; 33(2): 1004-1014, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36169689

RESUMEN

OBJECTIVES: Magnetic resonance imaging has high sensitivity in detecting early brainstem infarction (EBI). However, MRI is not practical for all patients who present with possible stroke and would lead to delayed treatment. The detection rate of EBI on non-contrast computed tomography (NCCT) is currently very low. Thus, we aimed to develop and validate the radiomics feature-based machine learning models to detect EBI (RMEBIs) on NCCT. METHODS: In this retrospective observational study, 355 participants from a multicentre multimodal database established by Huashan Hospital were randomly divided into two data sets: a training cohort (70%) and an internal validation cohort (30%). Fifty-seven participants from the Second Affiliated Hospital of Xuzhou Medical University were included as the external validation cohort. Brainstems were segmented by a radiologist committee on NCCT and 1781 radiomics features were automatically computed. After selecting the relevant features, 7 machine learning models were assessed in the training cohort to predict early brainstem infarction. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, F1-score, and the area under the receiver operating characteristic curve (AUC) were used to evaluate the performance of the prediction models. RESULTS: The multilayer perceptron (MLP) RMEBI showed the best performance (AUC: 0.99 [95% CI: 0.96-1.00]) in the internal validation cohort. The AUC value in external validation cohort was 0.91 (95% CI: 0.82-0.98). CONCLUSIONS: RMEBIs have the potential in routine clinical practice to enable accurate computer-assisted diagnoses of early brainstem infarction in patients with NCCT, which may have important clinical value in reducing therapeutic decision-making time. KEY POINTS: • RMEBIs have the potential to enable accurate diagnoses of early brainstem infarction in patients with NCCT. • RMEBIs are suitable for various multidetector CT scanners. • The patient treatment decision-making time is shortened.


Asunto(s)
Infartos del Tronco Encefálico , Aprendizaje Automático , Humanos , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos , Diagnóstico Precoz , Infartos del Tronco Encefálico/diagnóstico por imagen
3.
Neuroradiology ; 65(2): 297-305, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36208304

RESUMEN

PURPOSE: Neuroplasticity can partially compensate for the neurological deficits caused by brain tumors. However, the structural plasticity of the brain caused by brain tumors is not fully understood. This study aimed to assess the structural plasticity of the contralesional hemisphere in patients with frontal low-grade gliomas (LGGs). METHODS: A total of 25 patients with left frontal LGGs (LFLGGs), 19 patients with right frontal LGGs (RFLGGs), and 25 healthy controls (HCs) were enrolled in this study. High-resolution structural T1-weighted imaging and fluid attenuation inversion recovery were performed on all participants. Voxel-based morphometry (VBM) analysis was used to detect differences in the brain structural plasticity between patients with unilateral LGGs and HCs. RESULTS: VBM analysis revealed that compared with HCs, the gray matter volume (GMV) of the contralesional putamen and amygdala was significantly smaller and larger in the patients with RFLGGs and LFLGGs, respectively, while the GMVs of the contralesional cuneus and superior temporal gyrus (STG) were significantly larger in the patients with LFLGGs. The surviving clusters of the right hemisphere included 1357 voxels in the amygdala, 1680 voxels in the cuneus, 384 voxels in the STG, and 410 voxels in the putamen. The surviving clusters of the left hemisphere were 522 voxels in the amygdala and 320 voxels in the putamen. CONCLUSION: The unilateral frontal LGGs are accompanied by structural plasticity in the contralesional cortex and vary with tumor laterality. Contralesional structural reorganization may be one of the physiological basis for functional reorganization or compensation in the frontal LGGs.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Encéfalo/patología , Corteza Cerebral/patología , Sustancia Gris/patología , Glioma/patología , Imagen por Resonancia Magnética/métodos , Neoplasias Encefálicas/patología
4.
J Environ Manage ; 325(Pt B): 116394, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36323127

RESUMEN

Three parallel bioreactors were operated with different inoculation of activated sludge (R1), intertidal sludge (ItS) (R2), and ItS-added AS (R3), respectively, to explore the effects of ItS bioaugmentation on the formation of salt-tolerant aerobic granular sludge (SAGS) and the enhancement of COD removal performance. The results showed that compared to the control (R1-2), R3 promoted a more rapid development of SAGS with a cultivation time of 25 d. Following 110-day cultivation, R3 exhibited a higher granular diameter of 1.3 mm and a higher hydrophobic aromatic protein content than that in control. Compared to the control, the salt-tolerant performance in R3 was also enhanced with the COD removal efficiency of 96.4% due to the higher sludge specific activity of 14.4 g·gVSS-1·d-1 and the salinity inhibition constant of 49.3 gL-1. Read- and genome-resolved metagenomics together indicated that a higher level of tryptophan/tyrosine synthase gene (trpBD, tyrBC) and enrichment of the key gene hosts Rhodobacteraceae, Marinicella in R3, which was about 5.4-fold and 1.4-fold of that in control, could be the driving factors of rapid development of SAGS. Furthermore, the augmented salt-tolerant potential in R3 could result from that R1 was dominated by Rhodospirillaceae, Bacteroidales, which carried more trehalose synthase gene (otsB, treS), while the dominant members Rhodobacteraceae, Marinicella in R3 were main contributors to the glycine betaine synthase gene (ectC, betB, gbsA). This study could provide deeper insights into the rapid development and improved salt-tolerant potential of SAGS via bioaugmentation of intertidal sludge, which could promote the application of hypersaline wastewater treatment.


Asunto(s)
Aguas del Alcantarillado , Purificación del Agua , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Salinidad , Aerobiosis
5.
J Clin Lab Anal ; 36(1): e24080, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34914135

RESUMEN

BACKGROUND: COVID-19 has become a global pandemic, and close contacts and asymptomatic patients are worthy of attention. METHODS: A total of 1844 people in close contacts with 76 COVID-19 patients were investigated, and nasopharyngeal swabs and venous blood were collected for centralized medical quarantine observation. Real-time fluorescence was used to detect SARS-CoV-2 nucleic acid in nasopharyngeal swabs of all close contacts, and the colloidal gold method was used to detect serum-specific antibodies. Levels of IgM- and IgG-specific antibodies were detected quantitatively through chemiluminescence from the first nucleic acid turned negative date (0 week) and on weekly intervals of ≤1 week, 1-2 weeks, 2-3 weeks, 3-4 weeks, 4-5 weeks, 5-6 weeks, and 6-7 weeks. RESULTS: The total positive rate of the colloidal gold method (88.5%, 23/26) was significantly higher (χ2  = 59.182, p < 0.001) than that of the healthy control group (2.0%, 1/50). There was significant difference in IgG concentration at different time points (0-7 weeks) after negative nucleic acid conversion (χ2  = 14.034, p = 0.029). Serum IgG levels were significantly higher at weekly time points of 4-5 weeks (Z = -2.399, p = 0.016), 5-6 weeks (Z = -2.049, p = 0.040), and 6-7 weeks (Z = -2.197, p = 0.028) compared with 1-2 weeks after negative nucleic acid conversion. However, there was no significant difference (χ2  = 4.936, p = 0.552) in IgM concentration between time points tested (0-7 weeks) after negative nucleic acid conversion. The positive rates of IgM and IgG in asymptomatic patients (χ2  = 84.660, p < 0.001) were significantly higher than those in the healthy control group (χ2  = 9.201, p = 0.002) within 7 weeks of negative nucleic acid conversion. CONCLUSIONS: The IgG concentration in asymptomatic cases remained at a high level after nucleic acid turned negative. Nucleic acid detection combined with IgM and IgG antibody detection is an effective way to screen asymptomatic infections.


Asunto(s)
Prueba Serológica para COVID-19/métodos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Adulto , Anciano , COVID-19/epidemiología , Portador Sano/sangre , China/epidemiología , Femenino , Oro Coloide , Humanos , Masculino , Persona de Mediana Edad
6.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36499453

RESUMEN

Photocatalytic green hydrogen (H2) production through water electrolysis is deemed as green, efficient, and renewable fuel or energy carrier due to its great energy density and zero greenhouse emissions. However, developing efficient and low-cost noble-metal-free photocatalysts remains one of the daunting challenges in low-cost H2 production. Porous graphitic carbon nitride (gCN) nanostructures have drawn broad multidisciplinary attention as metal-free photocatalysts in the arena of H2 production and other environmental remediation. This is due to their impressive catalytic/photocatalytic properties (i.e., high surface area, narrow bandgap, and visible light absorption), unique physicochemical durability, tunable electronic properties, and feasibility to synthesize in high yield from inexpensive and earth-abundant resources. The physicochemical and photocatalytic properties of porous gCNs can be easily optimized via the integration of earth-abundant heteroatoms. Although there are various reviews on porous gCN-based photocatalysts for various applications, to the best of our knowledge, there are no reviews on heteroatom-doped porous gCN nanostructures for the photocatalytic H2 evolution reaction (HER). It is essential to provide timely updates in this research area to highlight the research related to fabrication of novel gCNs for large-scale applications and address the current barriers in this field. This review emphasizes a panorama of recent advances in the rational design of heteroatom (i.e., P, O, S, N, and B)-doped porous gCN nanostructures including mono, binary, and ternary dopants for photocatalytic HERs and their optimized parameters. This is in addition to H2 energy storage, non-metal configuration, HER fundamental, mechanism, and calculations. This review is expected to inspire a new research entryway to the fabrication of porous gCN-based photocatalysts with ameliorated activity and durability for practical H2 production.


Asunto(s)
Nanoestructuras , Porosidad , Metales , Hidrógeno
7.
Anal Chem ; 93(27): 9471-9479, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34180674

RESUMEN

Mitophagy is a vital biological process playing central roles in the regulation of metabolic activity and quality control of mitochondria. The presented dual-color fluorescent probes to directly monitor mitophagy were based on the optical response to pH change during mitophagy, but pH fluctuation may lead to interference. To overcome this, herein, two fluorescent probes (G-Mito, R-Lyso) were rationally designed to visualize mitophagy directly in a dual-color manner, relying on the Förster resonance energy transfer (FRET) process for the first time. Green emissive G-Mito targeted and anchored the mitochondria via reaction with protein thiols. Red-emissive R-Lyso exclusively targeted lysosomes. Live cells loaded with the two probes demonstrated strong fluorescence in only the green channel with excitation at 405 nm. After mitophagy, G-Mito in mitochondria was delivered into the lysosomes, and red fluorescence evidently increased due to the FRET process. With the probes, mitochondria, lysosomes, and autolysosomes could be discriminatively visualized in three different sets of signals. Mitophagy induced by starvation and in normal physiological status were successfully observed. The probes revealed that a certain amount of H2O2 could induce mitophagy. We expect that the two probes can serve as molecular tools for validation of mitophagy and promote the development of related areas.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Mitofagia , Colorantes Fluorescentes/metabolismo , Peróxido de Hidrógeno/metabolismo , Lisosomas/metabolismo , Mitocondrias
8.
Int J Clin Pract ; 75(9): e14462, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34107113

RESUMEN

BACKGROUND AND PURPOSE: Studies have shown that some cytokines in COVID-19 patients were elevated. This study aims to assess whether IL-10, IL-1ß, IL-6, MCP-1, TNF-α, IP-10 and IL-4 serve as potential diagnostic biomarkers of COVID-19. METHODS: The above serum cytokines in COVID-19 patients and non-COVID-19 patients were detected by ELISA and SARS-CoV-2 IgM and IgG were detected by the chemiluminescence method. The independent-sample Mann-Whitney U test was utilised to compare cytokine levels in different groups and courses, the Levene T-test and T'-test were utilised to compare they in different genders and the Spearman correlation test was utilised to analyse the correlation between the cytokine levels with ages and SARS-CoV-2 IgG and IgM. RESULTS: Serum levels of IL-10, IL-1ß, MCP-1, TNF-α and IL-4 in COVID-19 patients were significantly higher than those in non-COVID-19 patients, while IL-6 were only significantly higher than in healthy people, IP-10 were significantly lower than in other diseases patients. AUCs of COVID-19 diagnosed by IL-10, IL-1ß, IL-6, MCP-1, TNF-α, IP-10 and IL-4 were 0.735, 0.775, 0.595, 0.821, 0.848, 0.38 and 0.682, respectively. In the COVID-19 patients' serum, the levels of IL-10 and MCP-1 of male were noticeably higher than those of female, and all cytokines were significantly positively correlated with age, IL-1ß and IL-4 were significantly negatively correlated with SARS-CoV-2 IgM, while IL-10, IL-1ß, IL-6, TNF- and IP-10 were significantly negatively correlated with SARS-CoV-2 IgG. IL-10 on 43-56 days was significantly lower than at 29-42 days, TNF-α at 15-42 days was significantly higher than at 0-14 days, IP-10 at 0-14 days was the highest and IL-4 at 29-42 days was significantly higher than at 0-14 days. CONCLUSIONS: The detection of IL-10, IL-1 ß, IL-6, MCP-1, TNF-α and IL-4 would assist the clinical study of COVID-19, and IP-10 may be the cytokine of early elevation in COVID-19 patients.


Asunto(s)
COVID-19 , Factor de Necrosis Tumoral alfa , Quimiocina CXCL10 , Citocinas , Femenino , Humanos , Interleucina-10 , Interleucina-1beta , Interleucina-4 , Interleucina-6 , Masculino , SARS-CoV-2
9.
Genomics ; 112(6): 4427-4434, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32745502

RESUMEN

It is urgent to find an effective antiviral drug against SARS-CoV-2. In this study, 96 virus-drug associations (VDAs) from 12 viruses including SARS-CoV-2 and similar viruses and 78 small molecules are selected. Complete genomic sequence similarity of viruses and chemical structure similarity of drugs are then computed. A KATZ-based VDA prediction method (VDA-KATZ) is developed to infer possible drugs associated with SARS-CoV-2. VDA-KATZ obtained the best AUCs of 0.8803 when the walking length is 2. The predicted top 3 antiviral drugs against SARS-CoV-2 are remdesivir, oseltamivir, and zanamivir. Molecular docking is conducted between the predicted top 10 drugs and the virus spike protein/human ACE2. The results showed that the above 3 chemical agents have higher molecular binding energies with ACE2. For the first time, we found that zidovudine may be effective clues of treatment of COVID-19. We hope that our predicted drugs could help to prevent the spreading of COVID.


Asunto(s)
Antivirales/metabolismo , Antivirales/farmacología , Evaluación Preclínica de Medicamentos/métodos , Simulación del Acoplamiento Molecular/métodos , SARS-CoV-2/efectos de los fármacos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/metabolismo , Alanina/farmacología , Enzima Convertidora de Angiotensina 2/química , Enzima Convertidora de Angiotensina 2/metabolismo , Antivirales/química , Interacciones Huésped-Patógeno/efectos de los fármacos , Humanos , Oseltamivir/metabolismo , Oseltamivir/farmacología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Zanamivir/metabolismo , Zanamivir/farmacología
10.
Environ Monit Assess ; 193(12): 814, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34787724

RESUMEN

Mining legacies continue to impact the geochemical cycles in historically mined watersheds after mine closure. The Hokuroku District in Northeast Japan is a famous metal mining area with a long mining history; however, studies on the distribution mechanisms and pollution characteristics of heavy metals in these historically mined watersheds after the boom period of mining activities are lacking. This study aims to provide fundamental insights into the effects of the mining activities and hydrological conditions on heavy metal pollution in the Kosaka watershed, Hokuroku District. Sampling was performed in terms of watershed segmentation, and the outlet of the tributary within each sub-watershed was also sampled to capture the diffusional pollution status. The distributions of Zn, Cu, Cd, Pb and As in river water and sediments, as well as their pollution characteristics and ecological risks, were analysed under different hydrological conditions. Our findings provide evidence of the ecological risk in surface water induced by Zn, Cu and Pb pollution in the Kosaka River system. In a high proportion of the sub-watershed, there was moderate to strong enrichment in Cd, Cu and Zn in the river sediments. The sub-watersheds with high pollution levels and ecological risk were highly consistent with the sub-watersheds encompassing abandoned mine sites. Suspended particles carried large amounts of Pb and Cu, especially on rainy days. The heavy metal contents in river water were very sensitive to occasional rainfall events; rainy days posed the most risk to organisms in the Kosaka River, followed by the low-water-level season and the high-water-level season.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Japón , Metales Pesados/análisis , Medición de Riesgo , Ríos , Agua , Contaminantes Químicos del Agua/análisis
11.
Small ; 16(7): e1906380, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31994342

RESUMEN

SrRuO3 as a rare conductive perovskite ruthenate has attracted increasing attention for application in energy conversion. Here, the electrocatalytic activity for the hydrogen evolution reaction (HER) of thermally synthesized layered SrRuO3 is investigated and shows a considerable activation during cathodic polarization in alkaline solution. The analysis demonstrates the electrode activation is caused by the increased hydrophilicity of SrRuO3 surface, revealing the influence of the surface properties on HER performance. For further improving the catalytic activity of perovskite ruthenate, the RuO2 /SrRuO3 (RSRO) heterostructure is fabricated in situ by reducing the thermal decomposition temperature of 1000 °C for SrRuO3 to 600 °C. The appropriate lattice parameter of SrRuO3 ensures a good lattice match, which results in a strong interaction between SrRuO3 and RuO2 . Hence, the RSRO substantially outperforms the corresponding single-component oxides. In addition, the increased active sites induced by the rapid improvement of hydrophilicity of RSRO surface further highlight its structural advantage for catalytic hydrogen generation. The experimental and theoretical computation results consistently validate the positive synergistic effect among SrRuO3 and RuO2 in tuning the atomic and electronic configuration.

12.
Anal Chem ; 91(2): 1524-1531, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30547579

RESUMEN

Ratiometric electrochemiluminescence (ECL) has attracted special focus in the biological analysis field, because it could eliminate the environmental interference and allow for precise measurement. Herein, a dual-wavelength ratiometric ECL biosensor was designed for the detection of cardiac troponin I (cTnI), where (4,4'-dicarboxylic acid-2,2'-bipyridyl) ruthenium(II) (Ru(dcbpy)32+) and Au nanoparticle-loaded graphene oxide/polyethylenimine (GPRu-Au) nanomaterial acts as an acceptor, and Au nanoparticle-modified graphitic phase carbon nitride nanosheet composite (Au-CNN) acts as donor. Au-CNN shows a high and steady ECL signal centered at 455 nm, which is well-matched with the adsorption of GPRu-Au; thereby, a highly efficient electrochemiluminescent resonance energy transfer (ECL-RET) sensing platform is designed. AuNPs facilitate the immobilization of antibody on the nanomaterials through a Au-N bond. The high surface area of graphene oxide/polyethylenimine allows a large number of Ru(dcbpy)32+ to be loaded, immensely amplifying the ECL signal. This sensing platform exhibits outstanding analytical performance toward cTnI with a detection limit of 3.94 fg/mL (S/N = 3). The high reliability, selectivity, and sensitivity of this ratiometric ECL biosensor provides a versatile sensing platform for the bioanalysis.


Asunto(s)
Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Miocardio/metabolismo , Troponina I/metabolismo , Electroquímica , Oro/química , Grafito/química , Humanos , Límite de Detección , Nanopartículas del Metal/química , Polietileneimina/química , Troponina I/química
13.
Appl Opt ; 58(29): 8013-8020, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31674355

RESUMEN

A portable Scheimpflug lidar system has been employed for atmospheric boundary layer studies. Atmospheric backscattering signals were continuously recorded from 21 August to 28 August 2018. The covariance wavelet transform (CWT) method was utilized to identify the maximum gradient of recorded lidar curves as the planetary boundary layer (PBL) height. As the directly retrieved PBL height could be underestimated or overestimated due to the presence of residual layers and thin clouds, localized atmospheric turbulence, aerosol stratification, etc., a CWT-based quality-control algorithm has also been developed to improve the reliability of the PBL height retrieval. The temporal distribution of the final PBL height has shown a clear diurnal variation as the ambient temperature changed due to the increasing and decreasing of surface heating during a one-week continuous measurement campaign. The promising results have shown great potential in employing the Scheimpflug lidar technique and the CWT-based method in the determination of the PBL height.

14.
Small ; 14(17): e1703642, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29611279

RESUMEN

Exploration of economical electrocatalysts for highly efficient and stable oxygen reduction reaction (ORR) is believed to be essential for diverse future renewable energy applications. Herein, cobalt sulfide nanowire core encapsulated in a N, S codoped graphitic carbon shell (CoS NWs@NSC) is successfully fabricated via the calcination of polydopamine-coated Co(CO3 )0.5 (OH)0.11 H2 O NWs with sulfur powder under argon atmosphere. The uniform encapsulation of CoS core by N, S codoped graphitic carbon shell favors the interaction of the core-shell structure for generating stable and numerous ORR active sites homogeneously dispersed throughout the materials. Meanwhile, the wire-like CoS NWs@NSC stacks to form 3D mesoporous conductive networks, which improves the mass and charge transport capability of catalyst. Accordingly, the resultant CoS NWs@NSC electrocatalysts possess excellent ORR activity through the four-electron pathway with superior stability and methanol tolerance over the Pt/C in 0.1 m KOH. This strategy can offer inspiration for designing and fabricating novel core-shell-structured nanomaterials with active sites derived from uniform morphology as potential electrocatalysts for various vital renewable energy devices.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 315: 124272, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38603960

RESUMEN

Visualization of cell apoptosis is a critical task playing central roles in the fundamental studies in biology, pathology, and biomedicine. Dual-emissive fluorescent probes are desired molecular tools for study on apoptosis, which however were rarely reported. Herein, utilizing the polarity differences between lysosomes and nucleus, a translocation type of fluorescent probe (NA-S) was developed for the dual-color visualization of cell apoptosis. NA-S was designed to be polarity sensitive, bearing alkalescence group, and with DNA affinity. In living cells, NA-S targeted the lysosomes to give blue fluorescence, which translocated into the nucleus during cell apoptosis to give green emission. Thereby, the cell apoptosis could be visualized with NA-S in dual-emissive manner. With the unique probe, the cell apoptosis induced by oxidative stress, UV irradiation, rotenone, colchicine, and paclitaxel have been successfully visualized.


Asunto(s)
Apoptosis , Núcleo Celular , Colorantes Fluorescentes , Lisosomas , Apoptosis/efectos de los fármacos , Lisosomas/metabolismo , Humanos , Colorantes Fluorescentes/química , Núcleo Celular/metabolismo , Espectrometría de Fluorescencia , Células HeLa , Estrés Oxidativo , Colchicina/farmacología , Rotenona/farmacología , Paclitaxel/farmacología
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124095, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38490121

RESUMEN

Cell apoptosis is a crucial physiological process playing central roles in key biological and pathological activities. However, the current fluorescent probes for the detection of late apoptosis were "off-on" probes, which were facilely interfered by false positive signals caused by inhomogeneous staining and other factors. Herein, a unique fluorescent probe (NPn) discriminating late apoptosis from early apoptosis and heathy status with two different sets of fluorescent signals have been prepared, to overcome the possible false positive signals. NPn was designed impermeable to biomembranes and simultaneously with high affinity to DNA/RNA, which localized on the plasma membranes of living and early apoptotic cells, while relocated to the nucleus in late apoptotic cells. The hydrophilic amine unit and small ion radius were responsive for its membrane impermeability, which was confirmed with two control molecules without amine group. Using the probe, we have successfully evaluated the cell apoptosis induced by ultraviolet irradiation, rotenone, colchicine, and paclitaxel, demonstrating its potential application in biological researches.


Asunto(s)
Apoptosis , Colorantes Fluorescentes , Colorantes Fluorescentes/metabolismo , Membrana Celular/metabolismo , Paclitaxel/metabolismo , Aminas
18.
ACS Appl Mater Interfaces ; 16(15): 18768-18781, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38588442

RESUMEN

Electrocatalytic hydrogen evolution reactions (HER) are envisaged as the most promising sustainable approach for green hydrogen production. However, the considerably high cost often associated with such reactions, particularly upon scale-up, poses a daunting challenge. Herein, a facile, effective, and environmentally benign one-pot scalable approach is developed to fabricate MnM (M═Co, Cu, Ni, and Fe) nanocrystals supported over in situ formed carbon nanofibers (MnM/C) as efficient noble-metal-free electrocatalysts for HER. The formation of carbon nanofibers entails impregnating cellulose in an aqueous solution of metal precursors, followed by annealing the mixture at 550 °C. During the impregnation process, cellulose acts as a reactor for inducing the in situ reductions of MnM salts with the assistance of ether and hydroxyl groups to drive the mass production (several grams) of ultralong (5 ± 1 µM) carbon nanofibers ornamented with MnM nanoparticles (10-14 nm in size) at an average loading of 2.87 wt %. For better electrocatalytic HER benchmarking, the fabricated catalysts were tested over different working electrodes, i.e., carbon paper, carbon foam, and glassy carbon, in the presence of different electrolytes. All the fabricated MnM/C catalysts have demonstrated an appealing synergetic-effect-dependent HER activity, with MnCo/C exhibiting the best performance over carbon foam, close to that of the state-of-the-art commercial Pt/C (10 wt % Pt), with an overpotential of 11 mV at 10 mA cm-2, a hydrogen production rate of 2448 mol g-1 h-1, and a prolonged stability of 2 weeks. The HER performance attained by MnCo/C nanofibers is among the highest reported for Pt-free electrocatalysts, thanks to the mutual alloying effect, higher synergism, large surface area, and active interfacial interactions over the nanofibers. The presented findings underline the potential of our approach for the large-scale production of cost-effective electrocatalysts for practical HER.

19.
Chest ; 165(6): e163-e167, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38852972

RESUMEN

This novel report presents the first known case, to our knowledge, of a 16-year-old male patient who experienced intraventricular thrombosis and pulmonary embolism after a Nuss procedure for pectus excavatum, attributed to chronic bar displacement. Two years after the operation, the patient experienced post-exercise cough and hemoptysis, which led to his admission. Imaging revealed pulmonary embolism, thrombosis in the right ventricular outflow tract, and lung infiltrative lesions. We hypothesize that the chronic bar displacement led to its embedment in the right ventricle, resulting in thrombus formation, which subsequently contributed to partial pulmonary embolism. Surgery revealed the bars' intrusion into the right ventricle and lung. This case highlights the risk of severe complications from bar displacement in the Nuss procedure, which necessitates long-term follow-up evaluation, caution against strenuous activities after surgery, and use of thoracoscopic guidance during bar implantation and removal. It underscores the importance of vigilant evaluation for late-stage complications in patients with respiratory distress or thrombosis after a Nuss procedure.


Asunto(s)
Tórax en Embudo , Embolia Pulmonar , Trombosis , Humanos , Embolia Pulmonar/etiología , Embolia Pulmonar/diagnóstico , Masculino , Adolescente , Tórax en Embudo/cirugía , Trombosis/etiología , Trombosis/diagnóstico por imagen , Trombosis/diagnóstico , Ventrículos Cardíacos/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico , Tomografía Computarizada por Rayos X
20.
Hepatogastroenterology ; 60(127): 1698-704, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24634939

RESUMEN

BACKGROUND/AIMS: The present study is to evaluate the roles of HBV infection, host factors and their interactions in the development of ultrasound-diagnosed fatty liver in Fujian province of China, a highly HBV endemic area. METHODOLOGY: From June 2007 to May 2008, 527 ultrasound-diagnosed fatty liver patients and 1042 controls were ultrasonically diagnosed in this hospital-based case-control study. Their demographic, anthropometric, biochemical, behavioral factors and HBV markers were compared, and factors associated with fatty liver were determined by multivariate logistic regression analysis. RESULTS: Multivariate ORs and 95% confidence intervals (Cls) of fatty liver were 3.96 (2.10-7.48) for HBsAg positivity, 2.97 (1.78-4.94) for HBsAg negativity with antibodies positivity (either anti-HBe or anti-HBc or both), 1.66 (1.10-2.51) for low alcohol consumption, 7.09 (4.28- 11.75) for obesity, 3.19 (1.75-5.81) for reduced high density lipoprotein cholesterol (HDL-C), 2.17 (1.00-4.72) for elevated fasting plasma glucose (FPG), 2.71 (1.72-4.27) for hypertriglyceridemia, 9.19 (4.32-19.57) for hypertension, and 2.89 (1.86-4.48) for hyperuricemia. Furthermore, synergistic interactions on the additive model were observed between HBV infection and obesity, hypertriglyceridemia, reduced HDL-C, and hyperuricemia with regard to the risk of fatty liver. CONCLUSIONS: Ultrasound-diagnosed fatty liver in Fujian province of China is closely associated with HBV infection, low alcohol consumption, obesity, and other features of the metabolic syndrome. In addition, HBV infection was synergistic with obesity, hypertriglyceridemia, reduced HDL-C, and hyperuricemia as far as the risk of fatty liver concerned.


Asunto(s)
Hígado Graso/diagnóstico por imagen , Hepatitis B/epidemiología , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Biomarcadores/sangre , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , China , HDL-Colesterol/sangre , Enfermedades Endémicas , Hígado Graso/epidemiología , Hígado Graso/virología , Femenino , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis B/virología , Humanos , Hipertrigliceridemia/sangre , Hipertrigliceridemia/epidemiología , Hiperuricemia/epidemiología , Modelos Logísticos , Masculino , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , Análisis Multivariante , Enfermedad del Hígado Graso no Alcohólico , Obesidad/epidemiología , Oportunidad Relativa , Valor Predictivo de las Pruebas , Factores de Riesgo , Ultrasonografía
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