Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122
Filtrar
1.
Endosc Int Open ; 12(4): E585-E592, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38654965

RESUMEN

Background and study aims Alterations to interstitial cells of Cajal (ICC) and collagen fibrosis have been implicated in the pathogenesis of gastroparesis. We aimed to evaluate the feasibility and safety of pyloric muscle sampling during gastric peroral endoscopic myotomy (G-POEM) and the association between pyloric ICC density and degree of fibrosis with clinical outcomes. Patients and methods This was a single-center prospective study of gastroparetic patients who underwent G-POEM and intraprocedural pyloric muscle biopsies between January 2022 and April 2023. ICC count was estimated using CD117 stain and trichome for collagen fibrosis. Clinical response to G-POEM was defined as an improvement of ≥ 1 point on the Gastroparesis Cardinal Symptom Index. Results Fifty-six patients (median age 60 years, 71.4% women) underwent G-POEM (100% technical success; 71.4% clinical response). ICC depletion (< 10/high-power field) and fibrosis were encountered in 70.4% and 75% of the cases, respectively. There was no difference in mean ICC count between G-POEM responders vs. non-responders (7±3.6 vs. 7.7±3.3; P = 0.9). There was no association between ICC density or degree of fibrosis with the etiology of gastroparesis, duration of symptoms, gastric emptying rate, or pyloric impedance planimetry. Patients who did not respond to G-POEM had a significantly higher degree of moderate/severe fibrosis when compared with those who responded (81.3% vs. 25%; P = 0.0002). Conclusions Pyloric muscle biopsies during G-POEM was feasible and safe. ICC depletion and pyloric muscle fibrosis are common in gastroparetic patients. The degree of fibrosis may be related to pyloric dysfunction and clinical response to G-POEM. Additional studies are needed to confirm these results.

2.
Nucleic Acids Res ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647109

RESUMEN

Spatial transcriptome technologies have enabled the measurement of gene expression while maintaining spatial location information for deciphering the spatial heterogeneity of biological tissues. However, they were heavily limited by the sparse spatial resolution and low data quality. To this end, we develop a spatial location-supervised auto-encoder generator STAGE for generating high-density spatial transcriptomics (ST). STAGE takes advantage of the customized supervised auto-encoder to learn continuous patterns of gene expression in space and generate high-resolution expressions for given spatial coordinates. STAGE can improve the low quality of spatial transcriptome data and smooth the generated manifold of gene expression through the de-noising function on the latent codes of the auto-encoder. Applications to four ST datasets, STAGE has shown better recovery performance for down-sampled data than existing methods, revealed significant tissue structure specificity, and enabled robust identification of spatially informative genes and patterns. In addition, STAGE can be extended to three-dimensional (3D) stacked ST data for generating gene expression at any position between consecutive sections for shaping high-density 3D ST configuration.

3.
Front Med (Lausanne) ; 11: 1339368, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38646560

RESUMEN

Objective: To evaluate the clinical efficacy and safety of baloxavir marboxil tablets in the treatment of influenza A. Methods: According to a random sequence generated by computer software, 200 patients with confirmed influenza A were divided into a study group and a control group with 100 cases in each group. Group allocation was concealed using sealed envelopes. The study group was treated with oral administration of baloxavir marboxil tablets, 40 mg once. The control group was given oral oseltamivir capsules, 75 mg twice a day, for five consecutive days. The therapeutic effects, symptom disappearance time and adverse drug reactions of the two groups after 5 days of treatment were compared. Results: There was no significant difference in the total effective rate between the two groups (99% vs. 98%, p > 0.05). There was no significant difference in fever subsidence time (1.54 ± 0.66 d vs. 1.67 ± 0.71 d, p > 0.05), cough improvement time (2.26 ± 0.91 d vs. 2.30 ± 0.90 d, p > 0.05) and sore throat improvement time (2.06 ± 0.86 d vs. 2.09 ± 0.83 d, p > 0.05) between the two groups. There was no significant difference in the incidence of adverse drug reactions between the two groups (8% vs. 13%, p > 0.05). Conclusion: Baloxavir marboxil tablets can be effectively used in the treatment of patients with influenza A and have a similar efficacy and safety profile as oseltamivir capsules.

4.
Adv Mater ; : e2402337, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38458611

RESUMEN

Room-temperature sodium-sulfur (RT-Na/S) batteries are promising alternatives for next-generation energy storage systems with high energy density and high power density. However, some notorious issues are hampering the practical application of RT-Na/S batteries. Besides, the working mechanism of RT-Na/S batteries under practical conditions such as high sulfur loading, lean electrolyte, and low capacity ratio between the negative and positive electrode (N/P ratio), is of essential importance for practical applications, yet the significance of these parameters has long been disregarded. Herein, it is comprehensively reviewed recent advances on Na metal anode, S cathode, electrolyte, and separator engineering for RT-Na/S batteries. The discrepancies between laboratory research and practical conditions are elaborately discussed, endeavors toward practical applications are highlighted, and suggestions for the practical values of the crucial parameters are rationally proposed. Furthermore, an empirical equation to estimate the actual energy density of RT-Na/S pouch cells under practical conditions is rationally proposed for the first time, making it possible to evaluate the gravimetric energy density of the cells under practical conditions. This review aims to reemphasize the vital importance of the crucial parameters for RT-Na/S batteries to bridge the gaps between laboratory research and practical applications.

5.
Heliyon ; 10(5): e26022, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38455571

RESUMEN

Object: Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by aberrant activity of the immune system. Plasmacytoid dendritic cells (pDCs) which the main producer of activated type I interferon, are related to SLE disease activity. To investigate the mechanism of Langchuangding (LCD) improving SLE based on TLR7-IRF7-IFNα pathway. Methods: SLE patients were randomly divided into Chinese medicine combined with western medicine (CWM) group and western medicine (WM) group, to observe the effect of LCD. The percent of pDCs in peripheral blood of SLE patients were detected by flow cytometry, and the influence of LCD on gene expression in SLE patients were detected by gene microarray. Mouse bone marrow cells were differentiated into dendritic like cells (DLC), then divided into Blank, immune complex (IC), LCD and dexamethasone (DXM) group. Employed RT-qPCR to detect MyD88, and IRF7 mRNA, and western blotting to determinate TLR7, MyD88, and p-IRF7 proteins. The IFNα in SLE patients were detected by enzyme-linked immunosorbent assay (ELISA). Employ dual luciferase to observe the interferon stimulated response element (ISRE) gene. Results: pDCs in WM group was higher than that of CWM group. The plasma IFNα in CWM group was significantly lower than that in WM group. The gene microarray showed that the gene expression of IFNα related signaling pathway in peripheral blood mononuclear cell (PBMC) and genes related to activation and proliferation of immune cells were down-regulated after LCD treatment. The DLCs MyD88, and IRF7 mRNA were down-regulated, TLR7, MyD88, and p-IRF7 proteins were significantly reduced, and the supernatant IFNα was significantly decreased in LCD group. LCD were mildly inhibited activation of ISRE in 293T cells. Conclusions: In certain degree, LCD is beneficial to SLE patients. LCD therapy SLE may be through TLR7 signaling pathway, and IRF7 may be a promising therapeutic target for the treatment of SLE.

6.
Anal Chem ; 96(6): 2327-2332, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38308847

RESUMEN

Interference from nonspecific binding imposes a fundamental limit in the sensitivity of biosensors that is dependent on the affinity and specificity of the available sensing probes. The dynamic single-molecule sensing (DSMS) strategy allows ultrasensitive detection of biomarkers at the femtomolar level by identifying specific binding according to molecular binding traces. However, the accuracy in classifying binding traces is not sufficient from separate features, such as the bound lifetime. Here, we establish a DSMS workflow to improve the sensitivity and linearity by classifying molecular binding traces in surface plasmon resonance microscopy with multiple kinetic features. The improvement is achieved by correlation analysis to select key features of binding traces, followed by unsupervised k-clustering. The results show that this unsupervised classification approach improves the sensitivity and linearity in microRNA (hsa-miR155-5p, hsa-miR21-5p, and hsa-miR362-5p) detection to achieve a limit of detection at the subfemtomolar level.


Asunto(s)
Técnicas Biosensibles , MicroARNs , MicroARNs/genética , Técnicas Biosensibles/métodos , Resonancia por Plasmón de Superficie , Nanotecnología , Biomarcadores
8.
Gastrointest Endosc ; 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38184116

RESUMEN

BACKGROUND AND AIMS: Opioid-induced esophageal dysfunction (OIED) often presents as spastic esophageal disorders (SEDs) and esophagogastric junction outflow obstruction (EGJOO). The aim of this study was to evaluate and compare clinical outcomes of peroral endoscopic myotomy (POEM) for SEDs and EGJOO among opioid users and nonusers. METHODS: This propensity score (PS) matching study included consecutive opioid users and nonusers who underwent POEM for SEDs and EGJOO between January 2018 and September 2022. The following covariates were used for the PS calculation: age, sex, duration of symptoms, Eckardt score, type of motility disorder, and length of myotomy during POEM. Clinical response was defined as a post-POEM Eckardt score ≤3. RESULTS: A total of 277 consecutive patients underwent POEM during the study period. PS matching resulted in the selection of 64 pairs of patients strictly matched 1:1 (n = 128) with no statistically significant differences in demographic, baseline, or procedural characteristics or in the parameters considered for the PS between the 2 groups. Clinical response to POEM was significantly lower among opioid users (51 of 64 [79.7%]) versus nonusers (60 of 64 [93.8%]) (P = .03) at a median follow-up of 18 months. Among opioid users, higher opioid dose (>60 morphine milligram equivalents per day) was associated with a higher likelihood of failure to respond to POEM (odds ratio, 4.59; 95% confidence interval, 1.31-3.98; P = .02). CONCLUSIONS: Clinical response to POEM for SEDs and EGJOO is significantly lower among opioid users versus nonusers. There was a dose-relationship between opioids and response to POEM, with higher daily opioid usage associated with a higher likelihood of treatment failure.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38261491

RESUMEN

Cognitive computing explores brain mechanisms and develops brain-like computing models for cognitive processes. EEG measures brain activity, and EEG classification identifies patterns using machine learning algorithms. Combining EEG classification with cognitive computing offers insights into cognitive processes, brainmachine interfaces, and cognitive state monitoring. We propose (DreamCatcher Network) DCNet, a self-supervised learning method for diagnosing sleep disorders using EEG. DCNet autonomously learns comprehensive representations through contrast learning, reducing annotation time. The training process involves feature learning, classification, time-series contrast learning, and data enhancement. Experimental results on the Sleep-EDF dataset achieved 81.28% average accuracy. Validation on the HAR dataset showed model efficiency and scalability, with 92.51% accuracy on the test set. DCNet has the potential to revolutionize sleep disorder diagnosis and enhance the development of cognitive computing-enabled smart healthcare systems.

11.
Biosens Bioelectron ; 246: 115897, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38064994

RESUMEN

Molecular diagnostics play an important role in illness detection, prevention, and treatment, and are vital in point-of-care test. In this investigation, a novel CRISPR/Cas12a based small-molecule detection platform was developed using Antibody-Controlled Cas12a Biosensor (ACCBOR), in which antibody would control the trans-cleavage activity of CRISPR/Cas12a. In this system, small-molecule was labeled around the PAM sites of no target sequence(NTS), and antibody would bind on the labeled molecule to prevent the combination of CRISPR/Cas12a, resulting the decrease of trans-cleavage activity. Biotin-, digoxin-, 25-hydroxyvitamin D3 (25-OH-VD3)-labeled NTS and corresponding binding protein were separately used to verify its preformance, showing great universality. Finally, one-pot detection of 25-OH-VD3 was developed, exhibiting high sensitivity and excellent specificity. The limit of detection could be 259.86 pg/mL in serum within 30 min. This assay platform also has the advantages of low cost, easy operation (one-pot method), and fast detection (∼30 min), would be a new possibilities for the highly sensitive detection of other small-molecule targets.


Asunto(s)
Técnicas Biosensibles , Sistemas CRISPR-Cas , Anticuerpos , Bioensayo , Biotina
12.
Gastrointest Endosc ; 99(2): 177-185, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37500019

RESUMEN

BACKGROUND AND AIMS: Video analysis has emerged as a potential strategy for performance assessment and improvement. We aimed to develop a video-based skill assessment tool for peroral endoscopic myotomy (POEM). METHODS: POEM was deconstructed into basic procedural components through video analysis by an expert panel. A modified Delphi approach and 2 validation exercises were conducted to refine the POEM assessment tool (POEMAT). Twelve assessors used the final POEMAT version to grade 10 videos. Fully crossed generalizability (G) studies investigated the contributions of assessors, endoscopists' performance, and technical elements to reliability. G coefficients below .5 were considered unreliable, between .5 and .7 as modestly reliable, and above .7 as indicative of satisfactory reliability. RESULTS: After task deconstruction, discussions, and the modified Delphi process, the final POEMAT comprised 9 technical elements. G analysis showed low variance for endoscopist performance (.8%-24.9%) and high interrater variability (range, 63.2%-90.1%). The G score was moderately reliable (≥.60) for "submucosal tunneling" and "myotomy" and satisfactorily reliable (≥.70) for "active hemostasis" and "mucosal closure." CONCLUSIONS: We developed and established initial content and response process validity evidence for the POEMAT. Future steps include appraisal of the tool using a wider range of POEM videos to establish and improve the discriminative validity of this tool.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Acalasia del Esófago , Miotomía , Cirugía Endoscópica por Orificios Naturales , Humanos , Acalasia del Esófago/cirugía , Reproducibilidad de los Resultados , Resultado del Tratamiento , Esfínter Esofágico Inferior
13.
J Shoulder Elbow Surg ; 33(3): 628-639, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37981002

RESUMEN

BACKGROUND: The addition of epinephrine in irrigation fluid and the intravenous or local administration of tranexamic acid have independently been reported to decrease bleeding, thereby improving surgeons' visualization during arthroscopic shoulder procedures. No study has compared the effect of intravenous tranexamic acid, epinephrine in the irrigation fluid, or the combination of both tranexamic acid and epinephrine on visual clarity during shoulder arthroscopy with a placebo group. We hypothesized that intravenous tranexamic acid is more effective than epinephrine mixed in the irrigation fluid in improving visualization during shoulder arthroscopy, with no additive effect when both are used. METHODS: Patients aged ≥18 years undergoing shoulder arthroscopy were randomized into one of 4 study arms: (1) saline irrigation fluid (placebo); (2) epinephrine (0.33 mL of 1:1000 per liter) mixed in irrigation fluid (EPI); (3) 1 g intravenous tranexamic acid (TXA); and (4) epinephrine and tranexamic acid combined (TXA + EPI). Visualization was rated intraoperatively on a scale from 0, indicating poor clarity, to 3, indicating excellent clarity, every 15 minutes and overall. The primary outcome measure was the overall rating of visualization. A stepwise linear regression was performed using visualization as the dependent variable and independent variables including presence or absence of epinephrine and tranexamic acid, surgery duration, complexity, mean arterial pressure, increase in pump pressure, and volume of irrigation fluid. RESULTS: One hundred twenty-eight patients (mean age 56 years) were randomized. Mean visual clarity for the placebo, TXA, EPI, and TXA + EPI groups were 2.0 (±0.6), 2.0 (±0.6), 2.6 (±0.5), and 2.7 (±0.5), respectively (P < .001). The presence or absence of epinephrine was the most significant predictor of visual clarity (P < .001). Tranexamic acid presence or absence had no effect. No adverse events were recorded in any of the groups. CONCLUSION: Intravenous tranexamic acid is not an effective alternative to epinephrine in irrigation fluid to improve visualization during routine arthroscopic shoulder surgeries, and there is no additive effect when both are used.


Asunto(s)
Antifibrinolíticos , Articulación del Hombro , Ácido Tranexámico , Humanos , Adolescente , Adulto , Persona de Mediana Edad , Hombro/cirugía , Ácido Tranexámico/uso terapéutico , Artroscopía/métodos , Epinefrina , Articulación del Hombro/cirugía , Antifibrinolíticos/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Método Doble Ciego
15.
JMIR Med Educ ; 9: e48904, 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153785

RESUMEN

BACKGROUND: Large language models, such as ChatGPT, are capable of generating grammatically perfect and human-like text content, and a large number of ChatGPT-generated texts have appeared on the internet. However, medical texts, such as clinical notes and diagnoses, require rigorous validation, and erroneous medical content generated by ChatGPT could potentially lead to disinformation that poses significant harm to health care and the general public. OBJECTIVE: This study is among the first on responsible artificial intelligence-generated content in medicine. We focus on analyzing the differences between medical texts written by human experts and those generated by ChatGPT and designing machine learning workflows to effectively detect and differentiate medical texts generated by ChatGPT. METHODS: We first constructed a suite of data sets containing medical texts written by human experts and generated by ChatGPT. We analyzed the linguistic features of these 2 types of content and uncovered differences in vocabulary, parts-of-speech, dependency, sentiment, perplexity, and other aspects. Finally, we designed and implemented machine learning methods to detect medical text generated by ChatGPT. The data and code used in this paper are published on GitHub. RESULTS: Medical texts written by humans were more concrete, more diverse, and typically contained more useful information, while medical texts generated by ChatGPT paid more attention to fluency and logic and usually expressed general terminologies rather than effective information specific to the context of the problem. A bidirectional encoder representations from transformers-based model effectively detected medical texts generated by ChatGPT, and the F1 score exceeded 95%. CONCLUSIONS: Although text generated by ChatGPT is grammatically perfect and human-like, the linguistic characteristics of generated medical texts were different from those written by human experts. Medical text generated by ChatGPT could be effectively detected by the proposed machine learning algorithms. This study provides a pathway toward trustworthy and accountable use of large language models in medicine.


Asunto(s)
Algoritmos , Inteligencia Artificial , Humanos , Desinformación , Suministros de Energía Eléctrica , Instituciones de Salud
16.
Animals (Basel) ; 13(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38003068

RESUMEN

The aim of this study was to investigate the molecular mechanisms by which hypoxia affects the biological behavior of yak PASMCs, the changes in the histological structure of yak and cattle lungs, and the relationships and regulatory roles that exist regarding the differences in the distribution and expression of PDK1 and its hypoxia-associated factors screened for their role in the adaptation of yak lungs to the plateau hypoxic environment. The results showed that, at the level of transcriptome sequencing, the molecular regulatory mechanisms of the HIF-1 signaling pathway, glucose metabolism pathway, and related factors (HK2/PGK1/ENO1/ENO3/ALDOC/ALDOA) may be closely related to the adaptation of yaks to the hypoxic environment of the plateau; at the tissue level, the presence of filled alveoli and semi-filled alveoli, thicker alveolar septa and basement membranes, a large number of erythrocytes, capillary distribution, and collagen fibers accounted for all levels of fine bronchioles in the lungs of yaks as compared to cattle. A higher percentage of goblet cells was found in the fine bronchioles of yaks, and PDK1, HIF-1α, and VEGF were predominantly distributed and expressed in the monolayers of ciliated columnar epithelium in the branches of the terminal fine bronchioles of yak and cattle lungs, with a small amount of it distributed in the alveolar septa; at the molecular level, the differences in PDK1 mRNA relative expression in the lungs of adult yaks and cattle were not significant (p > 0.05), the differences in HIF-1α and VEGF mRNA relative expression were significant (p < 0.05), and the expression of PDK1 and HIF-1α proteins in adult yaks was stronger than that in adult cattle. PDK1 and HIF-1α proteins were more strongly expressed in adult yaks than in adult cattle, and the difference was highly significant (p < 0.01); the relative expression of VEGF proteins was not significantly different between adult yaks and cattle (p > 0.05). The possible regulatory relationship between the above results and the adaptation of yak lungs to the plateau hypoxic environment paves the way for the regulatory mechanisms of PDK1, HIF-1α, and VEGF, and provides basic information for studying the mechanism of hypoxic adaptation of yaks in the plateau. At the same time, it provides a reference for human hypoxia adaptation and a target for the prevention and treatment of plateau diseases in humans and plateau animals.

17.
BMC Pediatr ; 23(1): 602, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017394

RESUMEN

The objective of this study was to evaluate intraobserver reliability and inter-observer reproducibility of a 3-dimensional (3D) assessment method for mandibular changes of growing patients after orthodontic treatment for Class III malocclusion.Methods Cone-beam computed tomography (CBCT) scans were performed before and after orthodontic treatment for 27 patients. During the scan, the patient was positioned such that his/her mandibular plane was parallel to floor. Three observers independently worked on the DICOM data, reconstructed the pre- and post-treatment 3D models in software, selected the stable anatomical structures (basal bone area from the lingual surface of the symphysis to the distal aspect of the first molars) to guide the automated superimposition process. Then, each observer registered 14 anatomical landmarks on the virtual models, for three times after suitable interval, to generate 3 sets of coordinates; the mean was taken as the coordinates for that particular landmark. The intraobserver reliability and inter-observer reproducibility of the method were analyzed.Results The ICCs was > 0.90 for 25 (92.6%) of the intraobserver assessments. The precision of the measurement method was < 0.3 mm in 24 (88.9%) cases. The interobserver reproducibility errors were < 0.3 mm in 21 of the 27 cases.Conclusions The intraobserver reliability and inter-observer reproducibility of 3D assessment of mandibular changes using the virtual models were excellent.


Asunto(s)
Tomografía Computarizada de Haz Cónico Espiral , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Imagenología Tridimensional/métodos , Mandíbula/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Cefalometría
18.
Biomimetics (Basel) ; 8(7)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37999170

RESUMEN

The attainment of accurate motion control for robotic fish inside intricate underwater environments continues to be a substantial obstacle within the realm of underwater robotics. This paper presents a proposed algorithm for trajectory tracking and obstacle avoidance planning in robotic fish, utilizing nonlinear model predictive control (NMPC). This methodology facilitates the implementation of optimization-based control in real-time, utilizing the present state and environmental data to effectively regulate the movements of the robotic fish with a high degree of agility. To begin with, a dynamic model of the robotic fish, incorporating accelerations, is formulated inside the framework of the world coordinate system. The last step involves providing a detailed explanation of the NMPC algorithm and developing obstacle avoidance and objective functions for the fish in water. This will enable the design of an NMPC controller that incorporates control restrictions. In order to assess the efficacy of the proposed approach, a comparative analysis is conducted between the NMPC algorithm and the pure pursuit (PP) algorithm in terms of trajectory tracking. This comparison serves to affirm the accuracy of the NMPC algorithm in effectively tracking trajectories. Moreover, a comparative analysis between the NMPC algorithm and the dynamic window approach (DWA) method in the context of obstacle avoidance planning highlights the superior resilience of the NMPC algorithm in this domain. The proposed strategy, which utilizes NMPC, demonstrates a viable alternative for achieving precise trajectory tracking and efficient obstacle avoidance planning in the context of robotic fish motion control within intricate surroundings. This method exhibits considerable potential for practical implementation and future application.

19.
Anal Chim Acta ; 1283: 341849, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37977804

RESUMEN

Biomarkers are the most sensitive reactants and early indicators of many kinds of diseases. The development of highly sensitive and simple techniques to quantify them is challenging. In this study, based on rolling cycle amplification (RCA) and the Nicked PAM/CRISPR-Cas12a system (RNPC) as a signal reporter, a sandwich-type method was developed using antibody@magnetic beads and aptamer for the high-sensitive detection of the C-reactive protein (CRP). The antibody-antigen (target)-aptamer sandwich-like reaction was coupled to RCA, which can produce hundreds of similar binding sites and are discriminated by CRISPR/Cas12a for signal amplification. The ultrasensitivity is achieved based on the dual-signal enhancing strategy, which involves the special recognition of aptamers, RCA, and trans-cleavage of CRISPR/Cas12a. By incorporating the CRISPR/Cas12a system with cleaved PAM, the nonspecific amplification of the RCA reaction alone was greatly reduced, and the dual signal output of RCA and Cas12a improved the detection sensitivity. Our assay can be performed only in two steps. The first step takes only 20 min of target capture, followed by a one-pot reaction, where the target concentration can be obtained by fluorescence values as long as there are 37 °C reaction conditions. Under optimal conditions, this system detected CRP with high sensitivity. The fabricated biosensor showed detection limits of 0.40 pg/mL in phosphate-buffered saline and 0.73 pg/mL in diluted human serum and a broad linear dynamic range of 1.28 pg/mL to 100 ng/mL within a total readout time of 90 min. The method could be used to perform multi-step signal amplification, which can help in the ultrasensitive detection of other proteins. Overall, the proposed biosensor might be used as an immunosensor biosensor platform.


Asunto(s)
Técnicas Biosensibles , Sistemas CRISPR-Cas , Humanos , Sistemas CRISPR-Cas/genética , Inmunoensayo , Anticuerpos , Biomarcadores , Proteína C-Reactiva , Oligonucleótidos
20.
Org Lett ; 25(43): 7928-7932, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37870283

RESUMEN

α-H alkylation of carbonyls is a significant reaction in the pharmaceutical industry because it can directly form a C-C bond in an environmentally benign manner. Thus, developing a novel catalyst for this reaction is a hot and practical topic in catalysis, organic synthesis, and materials science. In this paper, we found that polyaniline-supported tungsten could catalyze the α-H alkylation reaction of ketone with alcohol generating water as the only byproduct. Polyaniline support is the key for promoting the catalytic activity of tungsten, which is relatively cheaper than the traditionally employed noble metals. The reaction occurred under mild conditions with a wide substrate scope. The substrate initial concentration was enhanced to 1 mol/L, while the reaction speed was accelerated to reduce the reaction time to only 6 h; these improvements could significantly enhance the production capacity. The advantages make this reaction practical for synthesis with industrial purposes.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...