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1.
Microbiome ; 12(1): 168, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39244633

RESUMEN

BACKGROUND: Next-generation sequencing (NGS) approaches have revolutionized gut microbiome research and can provide strain-level resolution, but these techniques have limitations in that they are only semi-quantitative, suffer from high detection limits, and generate data that is compositional. The present study aimed to systematically compare quantitative PCR (qPCR) and droplet digital PCR (ddPCR) for the absolute quantification of Limosilactobacillus reuteri strains in human fecal samples and to develop an optimized protocol for the absolute quantification of bacterial strains in fecal samples. RESULTS: Using strain-specific PCR primers for L. reuteri 17938, ddPCR showed slightly better reproducibility, but qPCR was almost as reproducible and showed comparable sensitivity (limit of detection [LOD] around 104 cells/g feces) and linearity (R2 > 0.98) when kit-based DNA isolation methods were used. qPCR further had a wider dynamic range and is cheaper and faster. Based on these findings, we conclude that qPCR has advantages over ddPCR for the absolute quantification of bacterial strains in fecal samples. We provide an optimized and easy-to-follow step-by-step protocol for the design of strain-specific qPCR assays, starting from primer design from genome sequences to the calibration of the PCR system. Validation of this protocol to design PCR assays for two L. reuteri strains, PB-W1 and DSM 20016 T, resulted in a highly accurate qPCR with a detection limit in spiked fecal samples of around 103 cells/g feces. Applying our strain-specific qPCR assays to fecal samples collected from human subjects who received live L. reuteri PB-W1 or DSM 20016 T during a human trial demonstrated a highly accurate quantification and sensitive detection of these two strains, with a much lower LOD and a broader dynamic range compared to NGS approaches (16S rRNA gene sequencing and whole metagenome sequencing). CONCLUSIONS: Based on our analyses, we consider qPCR with kit-based DNA extraction approaches the best approach to accurately quantify gut bacteria at the strain level in fecal samples. The provided step-by-step protocol will allow scientists to design highly sensitive strain-specific PCR systems for the accurate quantification of bacterial strains of not only L. reuteri but also other bacterial taxa in a broad range of applications and sample types. Video Abstract.


Asunto(s)
Heces , Microbioma Gastrointestinal , Limosilactobacillus reuteri , Humanos , Heces/microbiología , Microbioma Gastrointestinal/genética , Limosilactobacillus reuteri/genética , Limosilactobacillus reuteri/clasificación , Reproducibilidad de los Resultados , ADN Bacteriano/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Límite de Detección , Sensibilidad y Especificidad , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación
2.
ChemSusChem ; : e202400955, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255046

RESUMEN

As a globally abundant source of biomass, lignocellulosic biomass has been the centre of  attention as a potential resource for green energy generation and  value-added chemical production. A key component of lignocellulosic biomass, lignin, which is comprised of aromatic monomers, is a potential feedstock for value added chemical production. The cleavage processes of the linkages between monomers to obtain high value products, however, requires significant investigation as it is a complex, non-facile process. This study focuses on the photocatalytic valorization of a ß-5 lignin model compound, a key linkage in the lignin structure. It was found that a greater yield of aromatic products were obtained from the photocatalytic conversion of ß-5 lignin model compound using carbon nitride (CN) when compared to Evonik P25 titanium dioxide (TiO2). Products of the ß-5 model compound photoconversion were determined and C-C bond cleavage was observed. It was also determined that the solvent participated in the reactions with the introduction of a cyano group to one of the products. Radical quenching experiments revealed that superoxide radicals participated in the CN photocatalytic conversion. These results reveal for the first time the products and possible mechanism of the photocatalytic transformation of ß-5 model compounds using  CN photocatalysis.

4.
Ecotoxicol Environ Saf ; 284: 116939, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39191137

RESUMEN

Air pollution, particularly fine particulate matter and gaseous pollutants including NO2 and NOx, presents significant public health challenges. While the harmful effects of these pollutants are well-documented, the molecular mechanisms underlying their impact on health remain incompletely understood. In this study, we utilized genome-wide association study (GWAS) data from the UK Biobank, expression quantitative trait loci (eQTL) data from the Genotype-Tissue Expression (GTEx) project, and protein quantitative trait loci (pQTL) data from the Atherosclerosis Risk in Communities (ARIC) study to conduct comprehensive analyses using the Unified Test for Molecular Signatures (UTMOST), Transcriptome-wide Association Studies (TWAS), and Proteome-wide Association Studies (PWAS). To integrate and synthesize these analyses, we developed the AirSigOmniTWP Hub, a specialized platform designed to consolidate and interpret the results from UTMOST, TWAS, and PWAS. TWAS analysis identified a significant association between PM10 exposure and the gene INO80E in females (P = 4.37×10⁻5, FDR = 0.0383), suggesting a potential role in chromatin remodeling. PWAS analysis revealed a significant association between NOx exposure and the gene PIP in females (P = 2.28×10⁻5, FDR = 0.0299), implicating its involvement in inflammatory pathways. Additionally, UTMOST analyses uncovered significant associations between various pollutants and genes including NCOA4P3 and SPATS2L with PM2.5 exposure, indicating potential mechanisms related to transcriptional regulation and gene-environment interactions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Estudio de Asociación del Genoma Completo , Material Particulado , Sitios de Carácter Cuantitativo , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Humanos , Material Particulado/toxicidad , Contaminación del Aire/efectos adversos , Femenino , Masculino , Transcriptoma/efectos de los fármacos , Proteoma/efectos de los fármacos , Multiómica
5.
Biochem Biophys Res Commun ; 733: 150592, 2024 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-39213705

RESUMEN

Damage to oligodendrocytes (OLs) and myelin sheaths (demyelination) has been shown to be associated with numerous neurological and psychiatric disorders. Remyelination is a rare and reliable regenerative response that occurs in the central nervous system (CNS). It is generally believed that OL progenitor cells (OPCs) are the cell source to generate new OLs to remyelinate the demyelinated axons. However, several recent studies have argued that pre-existing mature OLs that survive within the demyelinated area are responsible for remyelination. Here, by conditional knock-out (KO) of a transcription factor gene that is essential for OPC differentiation, namely myelin regulatory factor (Myrf), to block the production of adult new OLs and examined its effect on remyelination after cuprizone (CPZ)-induced demyelination. We found that OPCs specific Myrf cKO mice show dramatic impairment in remyelination after 4 weeks of recovery from 5 weeks of CPZ diet and they leave over significant behavioral deficits such as anxiety-like behavior, decreased motor skills, and impaired memory compared to control mice that have recovered for the same time. Our data support the idea that OPCs are the major cell sources for myelin regeneration, suggesting that targeting the activation of OPCs and promoting their differentiation to boost new OLs production is critical for therapeutic intervention for demyelinating diseases such as multiple sclerosis (MS).


Asunto(s)
Cuprizona , Enfermedades Desmielinizantes , Ratones Noqueados , Oligodendroglía , Remielinización , Animales , Enfermedades Desmielinizantes/metabolismo , Enfermedades Desmielinizantes/patología , Enfermedades Desmielinizantes/genética , Enfermedades Desmielinizantes/inducido químicamente , Oligodendroglía/metabolismo , Oligodendroglía/patología , Cuprizona/toxicidad , Ratones , Vaina de Mielina/metabolismo , Conducta Animal , Ratones Endogámicos C57BL , Diferenciación Celular , Factores de Transcripción/metabolismo , Factores de Transcripción/genética
6.
Oxid Med Cell Longev ; 2024: 5632260, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139212

RESUMEN

This study aimed to investigate the mechanism of quercetin increasing growth performance and decreasing incidence of diarrhea in weaned piglets. Forty-eight Duroc × Landrace × Large White weaned piglets with similar body weight (7.48 ± 0.20 kg, 28 days of age) were randomly divided into four treatments (control, 250 mg/kg quercetin, 500 mg/kg quercetin, and 750 mg/kg quercetin treatments) and fed with basal diet or experimental diet supplemented with quercetin. Performance, diarrhea rate and index, and content of serum anti-inflammatory factors were determined and calculated in weaned piglets; colonic flora and signaling pathways related to anti-inflammation were measured using 16S rDNA sequencing and RNA-seq, respectively. The results showed that compared with control, feed-to-gain ratio and content of serum interferon gamma (IFN-γ) were significantly decreased in the 500 and 750 mg/kg quercetin treatments (P < 0.05); quercetin significantly decreased diarrhea rate and diarrhea index (P < 0.05) and significantly increased the content of serum transforming growth factor (TGF-ß) in weaned piglets (P < 0.05); the content of serum NF-κB was significantly decreased in the 750 mg/kg quercetin treatment (P < 0.05); moreover, quercetin significantly increased diversity of colonic flora (P < 0.05), and at the phylum level, the relative abundance of Actinobacteria in the 500 and 750 mg/kg treatments was significantly increased (P < 0.05), and the relative abundance of Proteobacteria in the three quercetin treatments were significantly decreased (P < 0.05) in the colon of weaned piglets; at the genus level, the relative abundance of Clostridium-sensu-stricto-1, Turicibacter, unclassified_f_Lachnospiraceae, Phascolarctobacterium, and Family_XIII _AD3011_group was significantly increased (P < 0.05); the relative abundance of Subdollgranulum and Blautia was significantly decreased in the 500 and 750 mg/kg treatments (P < 0.05); the relative abundance of Eschericha-Shigella, Terrisporobacter, and Eubacterium-coprostanoligenes was significantly increased (P < 0.05); the relative abundance of Streptocococcus, Sarcina, Staphylococcus, and Ruminococcaceae_UCG-008 was significantly decreased in the three quercetin treatments (P < 0.05); the relative abundance of Ruminococcaceae_UCG_014 was significantly increased in the 250 mg/kg quercetin treatment in the colon of weaned piglets (P < 0.05). The results of Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that differentially expressed genes (DEGs) from the quercetin treatments were significantly enriched in nuclear transcription factor-κB (NF-κB) signal pathway (P < 0.05); mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1R1 (IL-1R1), conserved helix-loop-helix ubiquitous kinase (CHUK), toll-like receptor 4 (TLR4), and IL-1ß from quercetin treatments were significantly decreased in colonic mucosa of weaned piglets (P < 0.05). In summary, quercetin increased feed conversion ratio and decreased diarrhea through regulating NF-κB signaling pathway, controlling the balance between anti-inflammatory and proinflammatory factors, and modulating intestinal flora, thus promoting the absorption of nutrients in weaned piglets. These results provided the theoretical foundation for applying quercetin in preventing weaning piglets' diarrhea and animal husbandry practices.


Asunto(s)
Diarrea , Quercetina , Destete , Animales , Quercetina/farmacología , Quercetina/uso terapéutico , Porcinos , Diarrea/veterinaria , Diarrea/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/tratamiento farmacológico , Incidencia
7.
Brain Res ; 1843: 149136, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39098577

RESUMEN

Sensory experience affects not only the corresponding primary sensory cortex, but also synaptic and neural circuit functions in other brain regions in a cross-modal manner. However, it remains unclear whether oligodendrocyte (OL) generation and myelination can also undergo cross-modal modulation. Here, we report that while early life short-term whisker deprivation from birth significantly reduces in the number of mature of OLs and the degree of myelination in the primary somatosensory cortex(S1) at postnatal day 14 (P14), it also simultaneously affects the primary visual cortex (V1), but not the medial prefrontal cortex (mPFC) with a similar reduction. Interestingly, when mice were subjected to long-term early whisker deprivation from birth (P0) to P35, they exhibited dramatically impaired myelination and a deduced number of differentiated OLs in regions including the S1, V1, and mPFC, as detected at P60. Meanwhile, the process complexity of OL precursor cells (OPCs) was also rduced, as detected in the mPFC. However, when whisker deprivation occurred during the mid-late postnatal period (P35 to P50), myelination was unaffected in both V1 and mPFC brain regions at P60. In addition to impaired OL and myelin development in the mPFC, long-term early whisker-deprived mice also showed deficits in social novelty, accompanied by abnormal activation of c-Fos in the mPFC. Thus, our results reveal a novel form of cross-modal modulation of myelination by sensory experience that can lead to abnormalities in social behavioral, suggesting a possible similar mechanism underlying brain pathological conditions that suffer from both sensory and social behavioral deficits, such as autism spectrum disorders.


Asunto(s)
Ratones Endogámicos C57BL , Vaina de Mielina , Corteza Prefrontal , Privación Sensorial , Corteza Somatosensorial , Vibrisas , Animales , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Vibrisas/fisiología , Privación Sensorial/fisiología , Vaina de Mielina/fisiología , Vaina de Mielina/metabolismo , Corteza Somatosensorial/fisiología , Ratones , Oligodendroglía/fisiología , Oligodendroglía/metabolismo , Animales Recién Nacidos , Masculino , Conducta Exploratoria/fisiología , Corteza Visual/crecimiento & desarrollo , Corteza Visual/metabolismo , Corteza Visual/fisiología , Conducta Social , Femenino
8.
Water Res ; 263: 122173, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39111213

RESUMEN

Wastewater treatment plants face significant challenges in transitioning from energy-intensive systems to carbon-neutral, energy-saving systems, and a large amount of chemical energy in wastewater remains untapped. Iron is widely used in modern wastewater treatment. Research shows that leveraging the coupled redox relationship of iron and carbon can redirect this energy (in the form of carbon) towards resource utilization. Therefore, re-examining the application of iron in existing wastewater carbon processes is particularly important. In this review, we investigate the latest research progress on iron for wastewater carbon flow restructuring. During the iron-based chemically enhanced primary treatment (CEPT) process, organic carbon is captured into sludge and its bioavailability is enhanced through iron-based advanced oxidation processes (AOP) pretreatment, further being recovered or upgraded to value-added products in anaerobic biological processes. We discuss the roles and mechanisms of iron in CEPT, AOP, anaerobic biological processes, and biorefining in driving organic carbon conversion. The dosage of iron, as a critical parameter, significantly affects the recovery and utilization of sludge carbon resources, particularly by promoting effective electron transfer. We propose a pathway for beneficial conversion of wastewater organic carbon driven by iron and analyze the benefits of the main products in detail. Through this review, we hope to provide new insights into the application of iron chemicals and current wastewater treatment models.


Asunto(s)
Carbono , Hierro , Eliminación de Residuos Líquidos , Aguas Residuales , Hierro/química , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Oxidación-Reducción , Aguas del Alcantarillado/química
9.
Light Sci Appl ; 13(1): 193, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152111

RESUMEN

High-power terahertz (THz) quantum cascade laser, as an emerging THz solid-state radiation source, is attracting attention for numerous applications including medicine, sensing, and communication. However, due to the sub-wavelength confinement of the waveguide structure, direct beam brightness upscaling with device area remains elusive due to several mode competition and external optical lens is normally used to enhance the THz beam brightness. Here, we propose a metallic THz photonic crystal resonator with a phase-engineered design for single mode surface emission over a broad area. The quantum cascade surface-emitting laser is capable of delivering an output peak power over 185 mW with a narrow beam divergence of 4.4° × 4.4° at 3.88 THz. A high beam brightness of 1.6 × 107 W sr-1m-2 with near-diffraction-limited M2 factors of 1.4 in both vertical and lateral directions is achieved from a large device area of 1.6 × 1.6 mm2 without using any optical lenses. The adjustable phase shift between the lattices enables a stable and high-intensity surface emission over a broad device area, which makes it an ideal light extractor for large-scale THz emitters. Our research paves the way to high brightness solid-state THz lasers and facilitates new applications in standoff THz imaging, detection, and diagnosis.

10.
Ann Surg Oncol ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158641

RESUMEN

BACKGROUND: Although visceral pleural invasion, lymphovascular invasion, tumor spread through air spaces, and poor differentiation are pathological risk factors associated with unfavorable prognosis in patients with lung adenocarcinoma, the cumulative impact of these factors on prognosis remains unclear. METHODS: We enrolled 1532 patients with stage I lung adenocarcinoma. Patients were divided according to the number of risk factors as follows: Group A (without risk factors), Group B (one risk factor), and Group C (multiple risk factors). Moreover, we stratified patients into two subgroups based on tumor size (≤ 3 cm, 3-4 cm). Kaplan-Meier analysis was used to evaluate 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: Overall, 949, 404, and 179 patients were included in Groups A, B, and C, respectively. Group C had a larger tumor size and more cases of extrathoracic recurrence than the other groups. The 5-year DFS and OS gradually decreased across Groups A to C (DFS: 94.3%, 80.6%, and 64.3%, respectively, p < 0.001; OS: 97.2%, 92.7%, and 77%, respectively, p < 0.001). A similar trend was observed for tumors ≤ 3 cm in size (DFS: 95.2%, 83.2%, and 68.5%, respectively, p < 0.001; OS: 97.6%, 94.1%, and 79.6%, respectively, p < 0.001), but a less pronounced trend was observed for tumors between 3 and 4 cm in size (DFS: 72.1, 60.8, and 43.3%, respectively, p = 0.054; OS: 85.7, 82.1, and 64.7%, respectively, p = 0.16). CONCLUSIONS: Postoperative survival worsened with increasing pathological risk factors in patients with stage I lung adenocarcinoma, especially those with tumor size ≤ 3 cm.

11.
Pediatr Surg Int ; 40(1): 165, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954009

RESUMEN

OBJECTIVE: This study aims to examine the clinical characteristics and surgical management of pediatric testicular epidermoid cysts, thereby contributing to the existing body of knowledge pertinent to the diagnosis and therapeutic intervention s for this condition. METHODS: A retrospective analysis was conducted on the clinical records of 23 pediatric patients diagnosed with testicular epidermoid cysts, who were admitted to our institution between April 2013 and February 2024. Concurrently, a comprehensive review and analysis of pertinent literature were undertaken to augment the findings. RESULTS: The mean age at which the onset of epidermoid cysts was observed was 6.0 years. All cases were singular and unilateral. B-ultrasound diagnosis categorized 6 cases as epidermoid cysts, 11 as teratomas, and 6 as indeterminate, yielding a diagnostic sensitivity of 26.1%. All patients underwent testicle-sparing mass resection, and nine patients underwent rapid intraoperative frozen section analysis, revealing eight cases of testicular epidermoid cysts and one teratoma, with a diagnostic sensitivity of 88.89%. Postoperative histopathological examination confirmed the diagnosis of testicular epidermoid cyst. CONCLUSIONS: Pediatric testicular epidermoid cysts are an uncommon occurrence, primarily presenting as a painless scrotal mass, which can mimic the clinical features of malignant testicular tumors. Imaging modalities and histopathological assessment are pivotal in the diagnostic process for pediatric testicular epidermoid cysts. For cases where B-ultrasound is inconclusive, rapid intraoperative pathological examination should be considered.


Asunto(s)
Quiste Epidérmico , Enfermedades Testiculares , Humanos , Masculino , Quiste Epidérmico/cirugía , Quiste Epidérmico/diagnóstico , Quiste Epidérmico/diagnóstico por imagen , Estudios Retrospectivos , Niño , Preescolar , Enfermedades Testiculares/cirugía , Enfermedades Testiculares/diagnóstico , Enfermedades Testiculares/diagnóstico por imagen , Adolescente , Lactante , Testículo/diagnóstico por imagen , Testículo/cirugía , Testículo/patología , Ultrasonografía/métodos , Teratoma/cirugía , Teratoma/diagnóstico por imagen , Teratoma/diagnóstico
12.
Sci Rep ; 14(1): 17641, 2024 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085366

RESUMEN

We aimed to assess the cumulative incidences of cancer-specific mortality (CSM) in non-metastatic patients with non­muscle invasive urothelial bladder cancer (NMIUBC) and establish competing risk nomograms to predict CSM. Patient data was sourced from the Surveillance, Epidemiology, and End Results database, as well as the electronic medical record system in our institution to form the external validation cohort. Sub-distribution proportional hazards model was utilized to determine independent risk factors influencing CSM in non-metastatic NMIUBC patients. Competitive risk nomograms were constructed to predict 3-year, 5-year, and 8-year cancer-specific survival (CSS) in all patients group, TURBT group and cystectomy group, respectively. The discrimination and accuracy of the model were validated through the concordance index (C-index), the area under the receiver operating characteristic curve (AUC), and calibration curves. Decision curve analysis (DCA) and a risk stratification system was employed to evaluate the clinical utility of the model. Race, age, marital status, surgery in other sites, tumor size, histological type, histological grade, T stage and N stage were identified as independent risk factors to predict CSS in all patients group. The C-index for 3-year CSS was 0.771, 0.770 and 0.846 in the training, testing and external validation sets, respectively. The ROC curves showed well discrimination and the calibration plots were well fitted and consistent. Moreover, DCA demonstrated well clinical effectiveness. Altogether, the competing risk nomogram displayed excellent discrimination and accuracy for predicting CSS in non-metastatic NMIUBC patients, which can be applied in clinical practice to help tailor treatment plans and make clinical decisions.


Asunto(s)
Nomogramas , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/mortalidad , Masculino , Femenino , Anciano , Persona de Mediana Edad , Factores de Riesgo , Medición de Riesgo/métodos , Curva ROC , Cistectomía , Programa de VERF , Anciano de 80 o más Años , Invasividad Neoplásica , Estudios Retrospectivos , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/patología , Pronóstico
13.
ACS Omega ; 9(24): 25655-25667, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38911799

RESUMEN

The incorporation of nanomaterials generated from Prussian blue (PB) derivatives has emerged as a promising strategy to significantly improve the properties of energetic materials. In this study, we comprehensively investigated the influence of nanomaterials derived from PB on the thermal decomposition characteristics of energetic materials. To achieve this goal, we prepared nanomaterials using coprecipitation and heat treatment methods with PB derivatives as catalysts. Advanced techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller (BET) analysis for specific surface area and pore size, and X-ray photoelectron spectroscopy were employed to thoroughly characterize these nanomaterials. Differential scanning calorimetry was used to assess the thermal behavior of nitrocellulose (NC), and the relevant kinetic parameters were determined through thermal decomposition kinetics calculations and analysis. This work revealed the influence of catalysts on the NC decomposition process and provided comprehensive insights into the effect of integrating nanomaterials derived from PB derivatives on the thermal decomposition performance of NC. The results of this work demonstrated the possibility of using nanomaterials generated from PB derivatives as effective catalysts to enhance the thermal decomposition characteristics of NC, offering interesting opportunities for their application in the field of high-energy materials.

15.
Mikrochim Acta ; 191(7): 414, 2024 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904836

RESUMEN

The conventional electrochemical detection strategy for alpha-fetoprotein (AFP) is limited by the antigen-antibody (Ag-Ab) reactions and suffers from low sensitivity and poor reproducibility due to the inconsistency of Ab-modified electrodes. Herein, we designed and explored a sandwich-type electrochemical sensor for highly sensitive detection of AFP based on aptamer (Apt)-AFP-Ab interaction mode with silver@gold (Ag@Au) core-shell nanoparticles (NPs) as a signal amplifier. AuNPs were electrodeposited onto MXene (Ti3C2TX)-modified glassy carbon electrode (GCE) to get AuNPs/MXene/GCE and further used as the signal amplification substrate. The tetrahedral DNA-linked AFP aptamers were immobilized onto AuNPs/MXene/GCE surface via Au-S bonds and used as the sensing and recognition platform for AFP capturing. Ag@AuNPs with core-shell structures were synthesized, characterized, and bound with Ab as detection elements by catalyzing H2O2 reduction. In the presence of AFP, a stable Apt-AFP-Ab sandwich structure was formed owing to the high affinities of aptamer and Ab toward the target AFP. The catalytic current produced by H2O2 reduction increased linearly with the logarithm of AFP concentration from 5 × 10-4 ng/mL to 1 × 105 ng/mL, accompanied by a low detection limit (1.6 × 10-4 ng/mL). Moreover, the novel sandwich-type electrochemical sensor shows high sensitivity, outstanding selectivity, and promising performance in the analysis of actual samples, displaying a broad application prospect in bioanalysis.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Oro , Límite de Detección , Nanopartículas del Metal , Plata , alfa-Fetoproteínas , alfa-Fetoproteínas/análisis , alfa-Fetoproteínas/inmunología , Aptámeros de Nucleótidos/química , Oro/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Plata/química , Humanos , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno/química , Electrodos , ADN/química
16.
Plant Physiol Biochem ; 213: 108828, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38896914

RESUMEN

The NAC (NAM, ATAF, and CUC) is one of the largest transcription factor gene families in plants. In this study, 180, 141, and 131 NAC family members were identified from Saccharum complex, including S. officinarum, S. spontaneum, and Erianthus rufipilus. The Ka/Ks ratio of ATAF subfamily was all less than 1. Besides, 52 ATAF members from 12 representative plants were divided into three clades and there was only a significant expansion in maize. Surprisingly, ABA and JA cis-elements were abundant in hormonal response factor, followed by transcriptional regulator and abiotic stressor. The ATAF subfamily was differentially expressed in various tissues, under low temperature and smut pathogen treatments. Further, the ScATAF1 gene, with high expression in leaves, stem epidermis, and buds, was isolated. The encoded protein, lack of self-activation activity, was situated in the cell nucleus. Moreover, SA and JA stresses down-regulated the expression of this gene, while ABA, NaCl, and 4°C treatments led to its up-regulation. Interestingly, its expression in the smut susceptible sugarcane cultivars was much higher than the smut resistant ones. Notably, the colors presented slight brown in tobacco transiently overexpressing ScATAF1 at 1 d after DAB staining, while the symptoms were more obvious at 3 d after inoculation with Ralstonia solanacearum, with ROS, JA, and SA signaling pathway genes significantly up-regulated. We thus speculated ScATAF1 gene could negatively mediate hypersensitive reactions and produce ROS by JA and SA signaling pathways. These findings lay the groundwork for in-depth investigation on the biological roles of ATAF subfamily in sugarcane.


Asunto(s)
Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas , Proteínas de Plantas , Saccharum , Factores de Transcripción , Saccharum/genética , Saccharum/microbiología , Saccharum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Ralstonia solanacearum/fisiología , Filogenia
17.
Nat Commun ; 15(1): 4431, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789458

RESUMEN

Topological lasers (TLs) have attracted widespread attention due to their mode robustness against perturbations or defects. Among them, electrically pumped TLs have gained extensive research interest due to their advantages of compact size and easy integration. Nevertheless, limited studies on electrically pumped TLs have been reported in the terahertz (THz) and telecom wavelength ranges with relatively low output powers, causing a wide gap between practical applications. Here, we introduce a surface metallic Dirac-vortex cavity (SMDC) design to solve the difficulty of increasing power for electrically pumped TLs in the THz spectral range. Due to the strong coupling between the SMDC and the active region, robust 2D topological defect lasing modes are obtained. More importantly, enough gain and large radiative efficiency provided by the SMDC bring in the increase of the output power to a maximum peak power of 150 mW which demonstrates the practical application potential of electrically pumped TLs.

18.
J Hazard Mater ; 472: 134604, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38759283

RESUMEN

Of all chemical warfare agents (CWAs), only nerve and blood agents cause massive mortality at low concentrations. To better detect and discriminate nerve and blood agents, a reliable detection method is desirable. We report a series of fluorescent probes for nerve and blood agent detection. Among the tested probes, SR-Pip detected nerve and blood agents quickly (within 10 s for nerve agents and 1 min for blood agents). SR-Pip coupled with nerve agent produced a weak orange fluorescence with good sensitivity [limit of detection (LOD)= 5.5 µM]. Upon reaction with blood agent, the fluorescence of SR-Pip changed from orange fluorescence to blue fluorescence with detection limits as low as 9.6 nM. This probe effectively visualised different concentrations of nerve agents in living cells and mice. A portable test kit using SR-Pip instantly detected nerve and blood agents. To the best of our knowledge, SR-Pip is the first fluorescent probe for nerve and blood agent detection.


Asunto(s)
Sustancias para la Guerra Química , Colorantes Fluorescentes , Agentes Nerviosos , Animales , Colorantes Fluorescentes/química , Agentes Nerviosos/análisis , Agentes Nerviosos/toxicidad , Sustancias para la Guerra Química/análisis , Ratones , Humanos , Límite de Detección
19.
J Org Chem ; 89(10): 6694-6703, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38695196

RESUMEN

An excellent compatible and cost-effective dynamic kinetic resolution (DKR) protocol has been developed by combining a novel immobilized oxovanadium racemization catalyst onto cheap diatomite (V-D) with an immobilized lipase LA resolution catalyst onto a macroporous resin (LA-MR). V-D was prepared via grinding immobilization, which may become a promising alternative for the immobilization of metals, especially precious metals due to its low cost, high efficiency, easy separation, and large reaction interface. The DKR afforded high yield (96.1%), e.e. (98.67%), and Sel (98.28%) under optimal conditions established using response surface methodology as follows: the amount of V-D 10.83 mg, reaction time 51.2 h, and temperature 48.1 °C, respectively, indicating that all the reactions in the DKR were coordinated very well. The DKR protocol was also found to have high stability up to six reuses. V-D exhibited excellent compatibility with LA-MR because the lipase immobilized onto MR did not physically contact with the vanadium species immobilized onto diatomite, thus avoiding inactivation. Considering that lipase, oxovanadium, diatomite, and MR used are relatively inexpensive, and the adsorption or grinding immobilization is simple, the LA-V-MD DKR by coupling LA-MR with V-D is a cost-effective and promising protocol for chiral secondary alcohols.

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