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1.
Nano Lett ; 24(9): 2681-2688, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38408023

RESUMEN

Perovskite light-emitting diodes (PeLEDs) have emerged as promising candidates for lighting and display technologies owing to their high photoluminescence quantum efficiency and high carrier mobility. However, the performance of planar PeLEDs is limited by the out-coupling efficiency, predominantly governed by photonic losses at device interfaces. Most notably, the plasmonic loss at the metal electrode interfaces can account for up to 60% of the total loss. Here, we investigate the use of plasmonic nanostructures to improve the light out-coupling in PeLEDs. By integrating these nanostructures with PeLEDs, we have demonstrated an effectively reduced plasmonic loss and enhanced light out-coupling. As a result, the nanostructured PeLEDs exhibit an average 1.5-fold increase in external quantum efficiency and an ∼20-fold improvement in device lifetime. This finding offers a generic approach for enhancing light out-coupling, promising great potential to go beyond existing performance limitations.

2.
J Am Chem Soc ; 146(18): 12538-12546, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38656110

RESUMEN

There is growing acknowledgment that the properties of the electrochemical interfaces play an increasingly pivotal role in improving the performance of the hydrogen evolution reaction (HER). Here, we present, for the first time, direct dynamic spectral evidence illustrating the impact of the interaction between interfacial water molecules and adsorbed hydroxyl species (OHad) on the HER properties of Ni(OH)2 using Au/core-Ni(OH)2/shell nanoparticle-enhanced Raman spectroscopy. Notably, our findings highlight that the interaction between OHad and interfacial water molecules promotes the formation of weakly hydrogen-bonded water, fostering an environment conducive to improving the HER performance. Furthermore, the participation of OHad in the reaction is substantiated by the observed deprotonation step of Au@2 nm Ni(OH)2 during the HER process. This phenomenon is corroborated by the phase transition of Ni(OH)2 to NiO, as verified through Raman and X-ray photoelectron spectroscopy. The significant redshift in the OH-stretching frequency of water molecules during the phase transition confirms that surface OHad disrupts the hydrogen-bond network of interfacial water molecules. Through manipulation of the shell thickness of Au@Ni(OH)2, we additionally validate the interaction between OHad and interfacial water molecules. In summary, our insights emphasize the potential of electrochemical interfacial engineering as a potent approach to enhance electrocatalytic performance.

3.
Anal Chem ; 96(10): 4275-4281, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38409670

RESUMEN

Surface-enhanced Raman scattering (SERS) can overcome the existing technological limitations, such as complex processes and harsh conditions in gaseous small-molecule detection, and advance the development of real-time gas sensing at room temperature. In this study, a SERS-based hydrogen bonding induction strategy for capturing and sensing gaseous acetic acid is proposed for the detection demands of gaseous acetic acid. This addresses the challenges of low adsorption of gaseous small molecules on SERS substrates and small Raman scattering cross sections and enables the first SERS-based detection of gaseous acetic acid by a portable Raman spectrometer. To provide abundant hydrogen bond donors and acceptors, 4-mercaptobenzoic acid (4-MBA) was used as a ligand molecule modified on the SERS substrate. Furthermore, a sensing chip with a low relative standard deviation (RSD) of 4.15% was constructed, ensuring highly sensitive and reliable detection. The hydrogen bond-induced acetic acid trapping was confirmed by experimental spectroscopy and density functional theory (DFT). In addition, to achieve superior accuracy compared to conventional methods, an innovative analytical method based on direct response hydrogen bond formation (IO-H/Iref) was proposed, enabling the detection of gaseous acetic acid at concentrations as low as 60 ppb. The strategy demonstrated a superior anti-interference capability in simulated breath and wine detection systems. Moreover, the high reusability of the chip highlights the significant potential for real-time sensing of gaseous acetic acid.

4.
Anal Chem ; 96(17): 6784-6793, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38632870

RESUMEN

Hepatitis B virus (HBV) is a major cause of liver cirrhosis and hepatocellular carcinoma, with HBV surface antigen (HBsAg) being a crucial marker in the clinical detection of HBV. Due to the significant harm and ease of transmission associated with HBV, HBsAg testing has become an essential part of preoperative assessments, particularly for emergency surgeries where healthcare professionals face exposure risks. Therefore, a timely and accurate detection method for HBsAg is urgently needed. In this study, a surface-enhanced Raman scattering (SERS) sensor with a sandwich structure was developed for HBsAg detection. Leveraging the ultrasensitive and rapid detection capabilities of SERS, this sensor enables quick detection results, significantly reducing waiting times. By systematically optimizing critical factors in the detection process, such as the composition and concentration of the incubation solution as well as the modification conditions and amount of probe particles, the sensitivity of the SERS immune assay system was improved. Ultimately, the sensor achieved a sensitivity of 0.00576 IU/mL within 12 min, surpassing the clinical requirement of 0.05 IU/mL by an order of magnitude. In clinical serum assay validation, the issue of false positives was effectively addressed by adding a blocker. The final sensor demonstrated 100% specificity and sensitivity at the threshold of 0.05 IU/mL. Therefore, this study not only designed an ultrasensitive SERS sensor for detecting HBsAg in actual clinical serum samples but also provided theoretical support for similar systems, filling the knowledge gap in existing literature.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Espectrometría Raman , Antígenos de Superficie de la Hepatitis B/sangre , Espectrometría Raman/métodos , Humanos , Virus de la Hepatitis B/aislamiento & purificación , Nanopartículas del Metal/química , Hepatitis B/sangre , Hepatitis B/diagnóstico , Propiedades de Superficie , Límite de Detección
5.
Physiol Plant ; 176(4): e14506, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39191701

RESUMEN

Late embryogenesis abundant (LEA) proteins have been widely recognized for their role in various abiotic stress responses in higher plants. Nevertheless, the specific mechanism responsible for the function of LEA proteins in plants has not yet been explored. This research involved the isolation and characterization of HcLEA113 from kenaf, revealing a significant increase in its expression in response to drought stress. When HcLEA113 was introduced into yeast, it resulted in an improved survival rate under drought conditions. Furthermore, the overexpression of HcLEA113 in tobacco plants led to enhanced tolerance to drought stress. Specifically, HcLEA113-OE plants exhibited higher germination rates, longer root lengths, greater chlorophyll content, and higher relative water content under drought stress compared to wild-type (WT) plants, while their relative conductivity was significantly lower than that of WT plants. Further physiological measurements revealed that the proline content, soluble sugars, and antioxidant activities of WT and HcLEA113-OE tobacco leaves increased significantly under drought stress, with greater changes in HcLEA113-OE plants than WT. The increase in hydrogen peroxide (H2O2), superoxide anions (O2 -), and malondialdehyde (MDA) content was significantly lower in HcLEA113-OE lines than in WT plants. Additionally, HcLEA113-OE plants can activate reactive oxygen species (ROS)- and osmotic-related genes in response to drought stress. On the other hand, silencing the HcLEA113 gene through virus-induced gene silencing (VIGS) in kenaf plants led to notable growth suppression when exposed to drought conditions, manifesting as decreased plant height and dry weight. Meanwhile, antioxidant enzymes' activity significantly decreased and the ROS content increased. This study offers valuable insights for future research on the genetic engineering of drought resistance in plants.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Nicotiana , Proteínas de Plantas , Estrés Fisiológico , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/fisiología , Estrés Fisiológico/genética , Especies Reactivas de Oxígeno/metabolismo , Brassicaceae/genética , Brassicaceae/fisiología , Brassicaceae/metabolismo , Plantas Modificadas Genéticamente/genética , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Germinación/genética
6.
J Chem Phys ; 161(2)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-38973762

RESUMEN

Electrocatalytic CO2 reduction reaction (CO2RR) for CH4 production presents a promising strategy to address carbon neutrality, and the incorporation of a second metal has been proven effective in enhancing catalyst performance. Nevertheless, there remains limited comprehension regarding the fundamental factors responsible for the improved performance. Herein, the critical role of Pd in electrocatalytic CO2 reduction to CH4 on Cu-based catalysts has been revealed at a molecular level using in situ surface-enhanced Raman spectroscopy (SERS). A "borrowing" SERS strategy has been developed by depositing Cu-Pd overlayers on plasmonic Au nanoparticles to achieve the in situ monitoring of the dynamic change of the intermediate during CO2RR. Electrochemical tests demonstrate that Pd incorporation significantly enhances selectivity toward CH4 production, and the Faradaic efficiency (FE) of CH4 is more than two times higher than that for the catalysts without Pd. The key intermediates, including *CO2-, *CO, and *OH, have been directly identified under CO2RR conditions, and their evolution with the electrochemical environments has been determined. It is found that Pd incorporation promotes the activation of both CO2 and H2O molecules and accelerates the formation of abundant active *CO and hydrogen species, thus enhancing the CH4 selectivity. This work offers fundamental insights into the understanding of the molecular mechanism of CO2RR and opens up possibilities for designing more efficient electrocatalysts.

7.
Phytother Res ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39267167

RESUMEN

Long-term inflammation can cause chronic pain and trigger patients' anxiety by sensitizing the central nervous system. However, effective drugs with few side effects for treating chronic pain-induced anxiety are still lacking. The anxiolytic and anti-inflammatory effects of ruscogenin (RUS), an important active compound in Ophiopogon japonicus, were evaluated in a mouse model of chronic inflammatory pain and N9 cells. RUS (5, 10, or 20 mg/kg/day, i.g.) was administered once daily for 7 days after CFA injection; pain- and anxiety-like behaviors were assessed in mice. Anti-inflammatory effect of RUS (0.1, 1, 10 µM) on N9 microglia after LPS treatment was evaluated. Inflammatory markers (TNF-α, IL-1ß, IL-6, CD86, IL-4, ARG-1, and CD206) were measured using qPCR. The levels of IBA1, ROS, NF-κB, TLR4, P-IKK, P-IκBα, and P65, MAPKs (ERK, JNK, and P38), NLRP3 (caspase-1, ASC, and NLRP3) were detected by Western blotting or immunofluorescence staining. The potential target of RUS was validated by molecular docking and adeno-associated virus injection. Mice in CFA group exhibited allodynia and anxiety-like behaviors. LPS induced neuroinflammation in N9 cells. Both CFA and LPS increased the levels of IBA1, ROS, and inflammatory markers. RUS (10 mg/kg in vivo and 1 µM in vitro) alleviated these alterations through NF-κB/MAPKs/NLRP3 signaling pathways but had no effect on pain hypersensitivity. TLR4 strongly interacted with RUS, and TLR4 overexpression abolished the effects of RUS on anxiety and neuroinflammation. RUS exerts anti-inflammatory and anxiolytic effects via TLR4-mediated NF-κB/MAPKs/NLRP3 signaling pathways, which provides a basis for the treatment of chronic pain-induced anxiety.

8.
Bioprocess Biosyst Eng ; 47(7): 1027-1037, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38777954

RESUMEN

With the anoxic-aerobic membrane bioreactor (AO-MBR, CP) as a reference, high-throughput sequencing technology was used to reveal the characteristics of the microbial community structure in the anaerobic side-stream anoxic-aerobic membrane bioreactor sludge reduction process (AOMBR-ASSR, SRP). After the stable operation of two processes for 120 days, the average removal efficiencies of TN and TP in the effluent of SRP were increased by 5.6% and 29.8%, respectively. The observed sludge yields (Yobs) of the two processes were 0.14 and 0.17 gMLSS/(gCOD), respectively, and the sludge reduction rate of the SRP was 19.5%. Compared to the CP, the microbial richness and diversity index of SRP increased significantly. Chloroflexi, which is responsible for the degradation of organic substances under an anaerobic condition, seemed to be reduced in the SRP. Meanwhile, other phyla that involved in the nitrogen cycle, such as Nitrospirae and Planctomycetes, were found to be more abundant in the SRP than in the CP. A total of 21 identified classes were observed, and primarily hydrolyzed fermented bacteria (Sphingobacteriia, Betaproteobacteria, Actinobacteria and Deltaproteobacteria) and slow-growing microorganisms (Bacilli) were accumulated in the SRP. At the genus level, the inserted anaerobic side-stream reactor favored the hydrolyzed bacteria (Saprospiraceae, Rhodobacter and Candidatus_Competibacter), fermented bacteria (Lactococcus and Trichococcus), and slow-growing microorganisms (Dechloromonas and Haliangium), which play a crucial role in the sludge reduction. Furthermore, the enrichment of bacterial species related to nitrogen (Nitrospir and Azospira) provided the potential for nitrogen removal, while the anaerobic environment of the side-stream reactor promoted the enrichment of phosphorus-accumulating organisms.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Reactores Biológicos/microbiología , Aguas del Alcantarillado/microbiología , Anaerobiosis , Membranas Artificiales , Microbiota , Bacterias/metabolismo , Bacterias/genética , Bacterias/crecimiento & desarrollo , Bacterias/clasificación , Aerobiosis
9.
J Am Chem Soc ; 145(37): 20381-20388, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37668654

RESUMEN

Realizing the dual emission of fluorescence-phosphorescence in a single system is an extremely important topic in the fields of biological imaging, sensing, and information encryption. However, the phosphorescence process is usually in an inherently "dark state" at room temperature due to the involvement of spin-forbidden transition and the rapid non-radiative decay rate of the triplet state. In this work, we achieved luminescent harvesting of the dark phosphorescence processes by coupling singlet-triplet molecular emitters with a rationally designed plasmonic cavity. The achieved Purcell enhancement effect of over 1000-fold allows for overcoming the triplet forbidden transitions, enabling radiation enhancement with selectable emission wavelengths. Spectral results and theoretical simulations indicate that the fluorescence-phosphorescence peak position can be intelligently tailored in a broad range of wavelengths, from visible to near-infrared. Our study sheds new light on plasmonic tailoring of molecular emission behavior, which is crucial for advancing research on plasmon-tailored fluorescence-phosphorescence spectroscopy in optoelectronics and biomedicine.

10.
Acta Pharmacol Sin ; 44(5): 1029-1037, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36333557

RESUMEN

Pulmonary fibrosis (PF) is a chronic interstitial lung disease with no effective therapies. Galectin-3 (Gal-3), a marker of oxidative stress, plays a key role in the pathogenesis of PF. Fibroblast-myofibroblast differentiation (FMD) is an important source of fibrotic cells in PF. Previous studies showed that melatonin (MT) exerted anti-fibrotic effect in many diseases including PF through its antioxidant activity. In the present study we investigated the relationships among Gal-3, NRF2, ROS in FMD and their regulation by MT. We established an in vitro model of FMD in TGF-ß1-treated human fetal lung fibroblast1 (HFL1) cells and a PF mouse model via bleomycin (BLM) intratracheal instillation. We found that Gal-3 expression was significantly increased both in vitro and in vivo. Knockdown of Gal-3 in HFL1 cells markedly attenuated TGF-ß1-induced FMD process and ROS accumulation. In TGF-ß1-treated HFL1 cells, pretreatment with NRF2-specific inhibitor ML385 (5 µM) significantly increased the levels of Gal-3, α-SMA and ROS, suggesting that the expression of Gal-3 was regulated by NRF2. Treatment with NRF2-activator MT (250 µM) blocked α-SMA and ROS accumulation accompanied by reduced Gal-3 expression. In BLM-induced PF model, administration of MT (5 mg·kg-1·d-1, ip for 14 or 28 days) significantly attenuated the progression of lung fibrosis through up-regulating NRF2 and down-regulating Gal-3 expression in lung tissues. These results suggest that Gal-3 regulates TGF-ß1-induced pro-fibrogenic responses and ROS production in FMD, and MT activates NRF2 to block FMD process by down-regulating Gal-3 expression. This study provides a useful clue for a clinical strategy to prevent PF. Graphic abstract of the mechanisms. MT attenuated BLM-induced PF via activating NRF2 and inhibiting Gal-3 expression.


Asunto(s)
Melatonina , Fibrosis Pulmonar , Animales , Humanos , Ratones , Bleomicina/efectos adversos , Fibroblastos , Galectina 3/efectos de los fármacos , Galectina 3/metabolismo , Pulmón/patología , Melatonina/farmacología , Melatonina/uso terapéutico , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
11.
J Chem Phys ; 158(2): 024203, 2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36641419

RESUMEN

A rapid and accurate diagnostic modality is essential to prevent the spread of SARS-CoV-2. In this study, we proposed a SARS-CoV-2 detection sensor based on surface-enhanced Raman scattering (SERS) to achieve rapid and ultrasensitive detection. The sensor utilized spike protein deoxyribonucleic acid aptamers with strong affinity as the recognition entity to achieve high specificity. The spherical cocktail aptamers-gold nanoparticles (SCAP) SERS substrate was used as the base and Au nanoparticles modified with the Raman reporter molecule that resonates with the excitation light and spike protein aptamers were used as the SERS nanoprobe. The SCAP substrate and SERS nanoprobes were used to target and capture the SARS-CoV-2 S protein to form a sandwich structure on the Au film substrate, which can generate ultra-strong "hot spots" to achieve ultrasensitive detection. Analysis of SARS-CoV-2 S protein was performed by monitoring changes in SERS peak intensity on a SCAP SERS substrate-based detection platform. This assay detects S protein with a LOD of less than 0.7 fg mL-1 and pseudovirus as low as 0.8 TU mL-1 in about 12 min. The results of the simulated oropharyngeal swab system in this study indicated the possibility of it being used for clinical detection, providing a potential option for rapid and accurate diagnosis and more effective control of SARS-CoV-2 transmission.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Humanos , Glicoproteína de la Espiga del Coronavirus , Nanopartículas del Metal/química , Oro/química , Espectrometría Raman/métodos , COVID-19/diagnóstico , SARS-CoV-2 , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos
12.
Phytochem Anal ; 34(3): 317-328, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36691258

RESUMEN

INTRODUCTION: Atractylodes chinensis is a Chinese herb that is used in traditional medicine; it contains volatile components that have enormous potential for pharmaceutical, food, and cosmetic applications. The destruction of wild resources demands significant improvement in the quality of artificial cultivation of Atractylodes chinensis. However, little is known about the compositional differences in the volatile substances derived from the wild and cultivated varieties of Atractylodes chinensis. OBJECTIVES: We aimed to evaluate the specific components of Atractylodes chinensis and analyse the similarities and differences between the volatile components and metabolic pathways in the wild and cultivated varieties. MATERIAL AND METHODS: Metabolomic analysis using gas chromatography-mass spectrometry (GC-MS) was employed following the extraction of volatile components from Atractylodes chinensis using headspace solid-phase microextraction (HS-SPME). RESULTS: A total of 167 volatile metabolites were extracted, and 137 substances were matched with NIST and Wiley databases. Among them, 76 compounds exhibited significant differences between the two sources; these mainly included terpenes, aromatics, and esters. KEGG enrichment analysis indicated that the differential metabolites were primarily involved in the biosynthesis of secondary metabolites, terpene biosynthesis, and limonene and pinene degradation; all these pathways have geranyl diphosphate (GDP) as the common link. CONCLUSION: The total content of volatile substances extracted from wild Atractylodes chinensis was 2.5 times higher than that from the cultured variety; however, each source had different dominant metabolites. This study underscores the necessity for protecting wild Atractylodes chinensis resources, while enhancing the quality of cultivated Atractylodes chinensis.


Asunto(s)
Atractylodes , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Terpenos , Limoneno/análisis , Compuestos Orgánicos Volátiles/análisis
13.
J Asian Nat Prod Res ; 25(4): 357-368, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35787216

RESUMEN

The VEGF receptor is mock-coupled with a known active compound and the active groups of the inhibitor which can bind to VEGF were analyzed. Using asiatic acid as a lead compound, 10 novel skeleton candidate compounds were designed through introduction of the active groups onto the special location and synthesized simultaneously. Furthermore, the structure of these compounds was determined by 1H NMR, 13C NMR and MS and 9 compounds were identified as the new compounds. Moreover, the in vitro anti-tumor activities of these new compounds were determined by MTT assay on two cancer cell lines (HepG2 and SGC-7901). The results showed that compounds I1 and II2 have more potent anticancer activity than positive control drugs such as gefitinib and paclitaxel.


Asunto(s)
Antineoplásicos , Estructura Molecular , Antineoplásicos/farmacología , Relación Estructura-Actividad , Línea Celular Tumoral , Factor A de Crecimiento Endotelial Vascular/farmacología , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Simulación del Acoplamiento Molecular
14.
Anal Chem ; 94(27): 9578-9585, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35770422

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) has been widely applied in many fields as a sensitive vibrational fingerprint technique. However, SERS faces challenges in quantitative analysis due to the heterogeneity of hot spots. An internal standard (IS) strategy has been employed for correcting the variation of hot spots. However, the method suffers from limitations due to the competitive adsorption between the IS and the target analyte. In this work, we combined the IS strategy with the 3D hybrid nanostructures to develop a bifunctional SERS substrate. The substrate had two functional units. The bottom self-assembly layer consisted of Au@IS@SiO2 nanoparticles, which provided a stable reference signal and functioned as the calibration unit. The top one consisted of appropriate-sized Au octahedrons for the detection of target analytes, which was the detection unit. Within the 3D hybrid nanostructure, the calibration unit improved the SERS performance of the detection unit, which was demonstrated by the 6-fold increase of SERS intensity when compared with the 2D substrate. Meanwhile, the reproducibility of the detection was greatly improved by correcting the hot spot changes through the calibration unit. Two biomedical molecules of cotinine and creatinine in ultrapure water and artificial urine, respectively, were sensitively determined by the 3D hybrid substrate. We expect that the developed bifunctional 3D substrate will open up new ways to advance the applications of SERS.


Asunto(s)
Oro , Nanopartículas del Metal , Calibración , Oro/química , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Dióxido de Silicio , Espectrometría Raman/métodos
15.
Anal Chem ; 94(2): 1318-1324, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34928126

RESUMEN

Human pepsin is a digestive protease that plays an important role in the human digestive system. The secondary structure of human pepsin determines its bioactivity. Therefore, an in-depth understanding of human pepsin secondary structure changes is particularly important for the further improvement of the efficiency of human pepsin biological function. However, the complexity and diversity of the human pepsin secondary structure make its analysis difficult. Herein, a convenient method has been developed to quickly detect the secondary structure of human pepsin using a portable Raman spectrometer. According to the change of surface-enhanced Raman spectroscopy (SERS) signal intensity and activity of human pepsin at different pH values, we analyze the change of the human pepsin secondary structure. The results show that the content of the ß-sheet gradually increased with the increase in the pH in the active range, which is in good agreement with circular dichroism (CD) measurements. The change of the secondary structure improves the sensitivity of human pepsin SERS detection. Meanwhile, human pepsin is a commonly used disease marker for the noninvasive diagnosis of gastroesophageal reflux disease (GERD); the detection limit of human pepsin we obtained is 2 µg/mL by the abovementioned method. The real clinical detection scenario is also simulated by spiking pepsin solution in saliva, and the standard recovery rate is 80.7-92.3%. These results show the great prospect of our method in studying the protein secondary structure and furthermore promote the application of SERS in clinical diagnosis.


Asunto(s)
Reflujo Gastroesofágico , Pepsina A , Reflujo Gastroesofágico/diagnóstico , Humanos , Saliva/química , Espectrometría Raman/métodos
16.
Anal Chem ; 94(51): 17795-17802, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36511436

RESUMEN

Addressing the spread of coronavirus disease 2019 (COVID-19) has highlighted the need for rapid, accurate, and low-cost diagnostic methods that detect specific antigens for SARS-CoV-2 infection. Tests for COVID-19 are based on reverse transcription PCR (RT-PCR), which requires laboratory services and is time-consuming. Here, by targeting the SARS-CoV-2 spike protein, we present a point-of-care SERS detection platform that specifically detects SARS-CoV-2 antigen in one step by captureing substrates and detection probes based on aptamer-specific recognition. Using the pseudovirus, without any pretreatment, the SARS-CoV-2 virus and its variants were detected by a handheld Raman spectrometer within 5 min. The limit of detection (LoD) for the pseudovirus was 124 TU µL-1 (18 fM spike protein), with a linear range of 250-10,000 TU µL-1. Moreover, this assay can specifically recognize the SARS-CoV-2 antigen without cross reacting with specific antigens of other coronaviruses or influenza A. Therefore, the platform has great potential for application in rapid point-of-care diagnostic assays for SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Sistemas de Atención de Punto , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos
17.
Small ; 18(39): e2203513, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36008122

RESUMEN

Enhanced electrochemiluminescence (ECL) aims to promote higher sensitivity and obtain better detection limit. The core-shell nanostructures, owing to unique surface plasmon resonance (SPR) enabling distance-dependent strong localized electromagnetic field, have attracted rising attention in enhanced ECL research and application. However, the present structures usually with porous shell involve electrocatalytic activity from the metal core and adsorption effect from the shell, which interfere with practical SPR enhancement contribution to ECL signal. Herein, to exclude the interference and unveil exact SPR-enhanced effect, shell-isolated nanoparticles (SHINs) whose shell gets thicker and becomes pinhole-free are developed by modifying pH value and particles concentration. Furthermore, allowing for the distribution of hotspots and stronger enhancement, excitation intensity and ECL reaction layer thickness are mainly investigated, and several types of SHINs-enhanced ECL platforms are prepared to fabricate distinct hotspot distribution via electrostatic attraction (submonolayer) and a layer-by-layer deposition method (monolayer). Consequently, the strongest enhancement up to ≈250-fold is achieved by monolayer SHINs with 10 nm shell, and the platform is applied in a "turn-off" mode sensing for dopamine. The platform provides new guidelines to shell preparation, interface engineering and hotspots fabrication for superior ECL enhancement and analytical application with high performance.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Técnicas Biosensibles/métodos , Dopamina , Técnicas Electroquímicas/métodos , Oro/química , Mediciones Luminiscentes/métodos , Nanopartículas del Metal/química
18.
Nat Mater ; 20(9): 1210-1215, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33846584

RESUMEN

Research efforts of cavity quantum electrodynamics have focused on the manipulation of matter hybridized with photons under the strong coupling regime1-3. This has led to striking discoveries including polariton condensation2 and single-photon nonlinearity3, where the phonon scattering plays a critical role1-9. However, resolving the phonon scattering remains challenging for its non-radiative complexity. Here we demonstrate nonlinear phonon scattering in monolayer MoS2 that is strongly coupled to a plasmonic cavity mode. By hybridizing excitons and cavity photons, the phonon scattering is equipped with valley degree of freedom and boosted with superlinear enhancement to a stimulated regime, as revealed by Raman spectroscopy and our theoretical model. The valley polarization is drastically enhanced and sustained throughout the stimulated regime, suggesting a coherent scattering process enabled by the strong coupling. Our findings clarify the feasibility of valley-cavity-based systems for lighting, imaging, optical information processing and manipulating quantum correlations in cavity quantum electrodynamics2,3,10-17.

19.
BMC Psychiatry ; 22(1): 117, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35168584

RESUMEN

BACKGROUND: Although some psychological processes, such as stigma and self-efficacy, affect the complicated relationship between social support and depressive symptoms, few studies explored a similar psychological mechanism among individuals with substance use disorders (SUDs). Hence, this research investigates the mediating effects of stigma and the moderating effects of self-efficacy among the psychological mechanism that social support affects depressive symptoms. METHODS: The study included 1040 Chinese participants with SUDs and completed a series of self-report questionnaires. R software was used to organize and clean up data sets and analyze mediation and moderation effects. RESULTS: The result showed that stigma partially mediated depressive symptoms, while self-efficacy moderated this relationship. More specifically, less social support increased depression symptoms by bringing about higher stigma. Besides, subjects with higher self-efficacy are less susceptible to stigma and therefore have mild depressive symptoms. Furthermore, clinical and theoretical implications are discussed in our study. CONCLUSIONS: Chinese SUDs patients' depressive symptoms were indirectly affected by perceived social support via stigma and less affected by stigma with improved self-efficacy. The theoretical and practical implications of these results are discussed.


Asunto(s)
Depresión , Autoeficacia , Depresión/psicología , Humanos , Estigma Social , Apoyo Social , Encuestas y Cuestionarios
20.
Lung ; 200(1): 83-93, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35067758

RESUMEN

PURPOSE: To make a comprehensive population-based study on risk and prognostic factors of brain metastasis from lung cancer. METHODS: A total of 91,643 patients diagnosed with lung cancer from 2010 to 2018 were collected from the Surveillance, Epidemiology and End results (SEER) database. To analyze the risk and prognostic factors of brain metastasis among lung cancer patients, both Logistic and Cox regression methods were applied, respectively. Also, the competing risk regression model was performed to establish a new nomogram to predict cancer-specific survival (CSS). RESULTS: Among the 91,643 lung cancer patients, 10,855 were found to have brain metastasis, with the incidence of 11.84%. The residence, age, race, income, primary site, histological type, extracranial metastasis, T stage, and N stage were all found to be independent risk factors of brain metastasis. The median overall survival (OS) of brain metastasis patients was limited to 6.08 months. By dividing patients randomly into a primary cohort with 7237 patients and a validation cohort with 3618 patients, a conclusion that the income, race, gender, age, histological type, extracranial metastasis, T stage, and N stage were all associated with the prognosis of brain metastasis was drawn. Our established primary-cohort-based new nomogram showed a good discriminative ability in predicting the probability of CSS among patients with brain metastasis, and the C-index was 0.62. Besides, the calibration curves for CSS also showed that the predicted survival by nomogram was consistent with the actual survival in the validation cohort. CONCLUSION: Our study shall provide a deeper insight into the risk factors and prognosis of brain metastasis among lung cancer patients.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patología , Nomogramas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Programa de VERF
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