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1.
J Invertebr Pathol ; 207: 108202, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39322011

RESUMO

In the present study, a cryptic species (IchX) was isolated from the hemolymph of the Manila clam, Ruditapes philippinarum, collected from the west coast region of South Korea. Following comprehensive molecular analysis, a partial sequence resembling the small subunit of the ribosomal RNA (SSU rRNA) gene was obtained, indicating that this species belonged to the class Mesomycetozoea, also known as Ichthyosporea. Detailed phylogenetic analyses based on SSU rRNA sequences placed IchX in a distinct clade within the order Dermocystida, class Mesomycetozoea, and showed that IchX is closely related to Ichthyosporea sp. Microscopic examination of in vitro cultured IchX cells revealed life-cycle stages of different sizes, from the endospore to sporangium through vegetative stages. An ameboid-like structure was observed in the early endospore stages as the characteristic feature of zoospores. Ultrastructural analyses using scanning electron microscopy revealed that all endospores and vegetative cell stages are spherical. Transmission electron microscopy revealed characteristic features, including a spindle pole body and membrane-decorated hyaline vesicles, consistent with those previously described in Mesomycetozoea. In addition, a prominent fibrillar structure was observed. Notably, the cell wall of mature IchX sporangia was digested with 2 M NaOH, while that of the endospores was resistant. This is the first report of a novel Mesomycetozoean from the Manila clams. Further taxonomic study of this organism and elucidation of its pathological characteristics are necessary.

2.
Skin Res Technol ; 30(9): e70055, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39300791

RESUMO

BACKGROUND: Solar lentigo, a common epidermal hyperpigmented lesion found in sun-exposed areas, results from the proliferation of melanocytes and the accumulation of melanin. Although various treatments for solar lentigo have been explored, they often lead to complications, including prolonged erythema and post-inflammatory hyperpigmentation (PIH), posing significant concerns. OBJECTIVES AND METHODS: This study evaluated the safety and efficacy of the Vasculature Salvage Laser Surgery (VSLS) system. We treated six Korean patients, each with solar lentigo, in a single session using the 532-nm nanosecond neodymium-doped yttrium aluminum garnet (Nd:YAG) VSLS system, with follow-up periods ranging from 3 to 10 weeks. RESULTS: The treatment led to the complete removal of pigmented lesions in all patients without resulting in PIH, even in cases where previous laser treatments had failed. The only side effect observed was mild erythema, which resolved over the long term in most instances. CONCLUSIONS: The VSLS system emerges as a safe and effective treatment for pigmented lesions, including refractory solar lentigines. Nonetheless, additional studies are required to verify its long-term efficacy.


Assuntos
Lasers de Estado Sólido , Lentigo , Humanos , Feminino , Lasers de Estado Sólido/uso terapêutico , Lentigo/cirurgia , Masculino , Pessoa de Meia-Idade , Adulto , Resultado do Tratamento , Idoso , Terapia a Laser/métodos , Terapia a Laser/instrumentação , Luz Solar/efeitos adversos , Hiperpigmentação/cirurgia
3.
Int J Biometeorol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177805

RESUMO

Previous epidemiological studies have reported a short-term association between ambient temperature and suicide risk. To gain a clearer understanding of this association, it is essential to differentiate the risk factors for intentional self-harm (ISH) from those specifically associated with suicide deaths. Therefore, this study aims to examine whether the association between daily temperature and ISH or suicide deaths differs by age and sex. Between 2014 and 2019, cases of emergency room visits related to ISH and suicide deaths in Seoul were identified. A time-stratified case-crossover design was used to adjust for temporal trends and seasonal variation. A distributed lag nonlinear model was used to analyze the nonlinear and time-delayed effect of ambient temperature on ISH and suicide deaths. Positive associations were observed between temperature and both ISH and suicide deaths. For ISH, the relative risk (RR) was high at 1.17 (95% confidence interval (CI): 1.03, 1.34) for a temperature of 25.7 °C compared with 14.8 °C. The RR for suicide death was higher than those for ISH, at 1.43 (95% CI: 1.03, 2.00) for a temperature of 33.7 °C. These associations varied by age and sex, with males and females aged 35-64 years showing increased susceptibility to suicide deaths. This study provides detailed evidence that unusually high temperatures, both anomalous and out of season, may trigger suicidal behaviors, including both ISH and suicide deaths.

4.
Small ; : e2404283, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016994

RESUMO

Efficient sodium ion storage in graphite is as yet unattainable, because of the thermodynamic instability of sodium ion intercalates-graphite compounds. In this work, sodium fluorozirconate (Na3ZrF7, SFZ) functionalized graphite (SFZ-G) is designed and prepared by the in situ mechanochemical silicon (Si) replacement of sodium fluorosilicate (Na2SiF6, SFS) and functionalization of graphite at the same time. During the mechanochemical process, the atomic Si in SFS is directly replaced by atomic zirconium (Zr) from the zirconium oxide (ZrO2) balls and container in the presence of graphite, forming SFZ-G. The resulting SFZ-G, working as an anode material for sodium ion storage, shows a significantly enhanced capacity of 418.7 mAh g-1 at 0.1 C-rate, compared to pristine graphite (35 mAh g-1) and simply ball-milled graphite (BM-G, 200 mAh g-1). In addition, the SFZ-G exhibits stable sodium-ion storage performance with 86% of its initial capacity retention after 1000 cycles at 2.0 C-rate.

5.
J Phys Chem B ; 128(28): 6730-6741, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38968413

RESUMO

Fluorescent proteins (FPs) are essential tools for advanced microscopy techniques such as super-resolution imaging, single-particle tracking, and quantitative single-molecule counting. Various FPs fused to DNA-binding proteins have been used to observe the subcellular location and movement of specific gene loci in living and fixed bacterial cells. However, quantitative assessments of the properties of FPs for gene locus measurements are still lacking. Here, we assessed various FPs to observe specific gene loci in live and fixed Escherichia coli cells using a fluorescent repressor-operator binding system (FROS), tet operator-Tet repressor proteins (TetR). Tsr-fused FPs were used to assess the intensity and photostability of various FPs (five red FPs: mCherry2, FusionRed, mRFP, mCrimson3, and dKatushka; and seven yellow FPs: SYFP2, Venus, mCitrine, YPet, mClover3, mTopaz, and EYFP) at the single-molecule level in living cells. These FPs were then used for gene locus measurements using FROS. Our results indicate that TetR-mCrimson3 (red) and TetR-EYFP (yellow) had better properties for visualizing gene loci than the other TetR-FPs. Furthermore, fixation procedures affected the clustering of diffusing TetR-FPs and altered the locations of the TetR-FP foci. Fixation with formaldehyde consistently disrupted proper DNA locus observations using TetR-FPs. Notably, the foci measured using TetR-mCrimson3 remained close to their original positions in live cells after glyoxal fixation. This in vivo study provides a cell-imaging guide for the use of FPs for gene-locus observation in E. coli and a scheme for evaluating the use of FPs for other cell-imaging purposes.


Assuntos
Escherichia coli , Proteínas Luminescentes , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/química , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência , Loci Gênicos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/química
6.
Dalton Trans ; 53(27): 11295-11309, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38898716

RESUMO

A thiophene-derived Schiff base ligand (E)-2-morpholino-N-(thiophen-2-ylmethylene)ethanamine was used for the synthesis of M(II) complexes, [TEM(M)X2] (M = Co, Cu, Zn; X = Cl; M = Cd, X = Br). Structural characterization of the synthesized complexes revealed distorted tetrahedral geometry around the M(II) center. In vitro investigation of the synthesized ligand and its M(II) complexes showed considerable anti-urease and leishmanicidal potential. The synthesized complexes also exhibited a significant inhibitory effect on urease, with IC50 values in the range of 3.50-8.05 µM. In addition, the docking results were consistent with the experimental results. A preliminary study of human colorectal cancer (HCT), hepatic cancer (HepG2), and breast cancer (MCF-7) cell lines showed marked anticancer activities of these complexes.


Assuntos
Antineoplásicos , Complexos de Coordenação , Simulação de Acoplamento Molecular , Bases de Schiff , Tiofenos , Urease , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Urease/antagonistas & inibidores , Urease/metabolismo , Tiofenos/química , Tiofenos/farmacologia , Tiofenos/síntese química , Bases de Schiff/química , Bases de Schiff/farmacologia , Bases de Schiff/síntese química , Morfolinas/química , Morfolinas/farmacologia , Morfolinas/síntese química , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Estrutura Molecular , Leishmania/efeitos dos fármacos , Relação Estrutura-Atividade , Antiprotozoários/farmacologia , Antiprotozoários/química , Antiprotozoários/síntese química , Ensaios de Seleção de Medicamentos Antitumorais
7.
Adv Mater ; 36(35): e2404054, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925104

RESUMO

Particle size is a critical factor for improving photocatalytic reactivity of conjugated microporous polymers (CMPs) as mass transfer in the porous materials is often the rate-limiting step. However, due to the synthetic challenge of controlling the size of CMPs, the impact of particle size is yet to be investigated. To address this problem, a simple and versatile dispersion polymerization route that can synthesize dispersible CMP nanoparticles with controlled size from 15 to 180 nm is proposed. Leveraging the precise control of the size, it is demonstrated that smaller CMP nanoparticles have dramatically higher photocatalytic reactivity in various organic transformations, achieving more than 1000% enhancement in the reaction rates by decreasing the size from 180 to 15 nm. The size-dependent photocatalytic reactivity is further scrutinized using a kinetic model and transient absorption spectroscopy, revealing that only the initial 5 nm-thick surface layer of CMP nanoparticles is involved in the photocatalytic reactions because of internal mass transfer limitations. This finding substantiates the potential of small CMP nanoparticles to efficiently use photo-generated excitons and improve energy-efficiency of numerous photocatalytic reactions.

8.
ChemSusChem ; : e202401010, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842474

RESUMO

The ever-increasing demand for rechargeable battery systems in the era of electric vehicles has spurred extensive research into developing polymeric components for batteries, such as separators, polymer electrolytes, and binders. However, current battery systems rely on expensive and nonrenewable resources, which potentially have a negative environmental impact. Therefore, polymer materials derived from natural resources have gained significant attention, primarily due to their cost-effective and environmentally sustainable features. Moreover, natural feedstocks often possess highly polar functional groups and high molecular weights, offering desirable electro-chemo-mechanical features when applied as battery materials. More recently, various recycling and upcycling strategies for polymeric battery components have also been proposed given the substantial waste generation from end-of-life batteries. Recycling polymeric materials includes an overall process of recovering the components from spent batteries followed by regeneration into new materials. Polymer upcycling into battery materials involves transforming daily-used plastic waste into high-value-added battery components. This review aims to give a state-of-the-art overview of contemporary methods to develop sustainable polymeric materials and recycling/upcycling strategies for various battery applications.

9.
bioRxiv ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38659903

RESUMO

In eukaryotic cells, transcription, translation, and mRNA degradation occur in distinct subcellular regions. How these mRNA processes are organized in bacteria, without employing membrane-bound compartments, remains unclear. Here, we present generalizable principles underlying coordination between these processes in bacteria. In Escherichia coli, we found that co-transcriptional degradation is rare for mRNAs except for those encoding inner membrane proteins, due to membrane localization of the main ribonuclease, RNase E. We further found, by varying ribosome binding sequences, that translation affects mRNA stability not because ribosomes protect mRNA from degradation, but because low translation leads to premature transcription termination in the absence of transcription-translation coupling. Extending our analyses to Bacillus subtilis and Caulobacter crescentus, we established subcellular localization of RNase E (or its homolog) and premature transcription termination in the absence of transcription-translation coupling as key determinants that explain differences in transcriptional and translational coupling to mRNA degradation across genes and species.

10.
J Invertebr Pathol ; 204: 108119, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679368

RESUMO

This study reports the occurrence of Perkinsus marinus associated with wild Pacific oyster (Crassostrea gigas) specimens collected along the west coast of Korea. Confirmation of P. marinus presence was achieved by conventional PCR using World Organization of Animal Health (WOAH)-recommended primers that specifically targeted regions of the rDNA locus (ITS1, 5.8S, and ITS2). Sequencing of 10 samples revealed two distinct sequences differing by a single base pair, indicating potential haplotype variability. One sequence closely resembled the P. marinus strain found in Maryland, USA, whereas the other exhibited divergence, indicative of species diversity in the Korean strain, as was evident from the haplotype network analysis. Further validation involved the Ray's Fluid Thioglycollate Medium (RFTM) assay, which initially yielded inconclusive results, possibly due to low infection intensity. Subsequently, RFTM and 2 M NaOH assays conducted on the isolates in the present study, cultured P. marinus cells in standard DMEM/F12 medium, and a positive P. marinus strain (ATCC 50509), revealed characteristic hypnospores of P. marinus upon Lugol's iodine staining. These comprehensive investigations underscore the conclusive confirmation of P. marinus in Korean waters and mark a significant milestone in our understanding of the distribution and characteristics of this parasite in previously unreported regions.


Assuntos
Alveolados , Crassostrea , Animais , República da Coreia , Crassostrea/parasitologia , Alveolados/isolamento & purificação , Alveolados/genética
11.
Biosens Bioelectron ; 222: 114977, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516633

RESUMO

Rapid diagnostic tests (RDTs) have shown to be instrumental in healthcare and disease control. However, they have been plagued by many inefficiencies in the laborious empirical development and optimization process for the attainment of clinically relevant sensitivity. While various studies have sought to model paper-based RDTs, most have relied on continuum-based models that are not necessarily applicable to all operation regimes, and have solely focused on predicting the specific interactions between the antigen and binders. It is also unclear how the model predictions may be utilized for optimizing assay performance. Here, we propose a streamlined and simplified model-based framework, only relying on calibration with a minimal experimental dataset, for the acceleration of assay optimization. We show that our models are capable of recapitulating experimental data across different formats and antigen-binder-matrix combinations. By predicting signals due to both specific and background interactions, our facile approach enables the estimation of several pertinent assay performance metrics such as limit-of-detection, sensitivity, signal-to-noise ratio and difference. We believe that our proposed workflow would be a valuable addition to the toolset of any assay developer, regardless of the amount of resources they have in their arsenal, and aid assay optimization at any stage in their assay development process.


Assuntos
Técnicas Biossensoriais , Sensibilidade e Especificidade , Antígenos , Razão Sinal-Ruído , Kit de Reagentes para Diagnóstico , Ensaio de Imunoadsorção Enzimática
12.
ACS Nano ; 16(10): 17041-17048, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36223132

RESUMO

Substrate accessibility is a key limiting factor for the efficiency of heterogeneous photoredox catalysis. Recently, a high photoactive surface area of conjugated microporous polymer nanoparticles (CMP NPs) has made them promising candidates for overcoming the mass transfer limitation to achieve high photocatalytic efficiency. However, this potential has not been realized due to limited dispersibility of CMP NPs in many solvents, particularly in water. Here, we report a polymer grafting strategy that furnishes versatile hairy CMP NPs with enhanced solvent-specific dispersibility. The method associates hundreds of solvent-miscible repeating units with one chain end of the photocatalyst surface, allowing minimal modification to the CMP network that preserves its photocatalytic activity. Therefore, the enhanced dispersibility of hairy CMP NPs in organic solvents or aqueous solutions affords high efficiency in various photocatalytic organic transformations.

13.
Sci Rep ; 12(1): 11352, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35790841

RESUMO

This study investigated the usefulness of deep learning-based automatic detection of anterior disc displacement (ADD) from magnetic resonance imaging (MRI) of patients with temporomandibular joint disorder (TMD). Sagittal MRI images of 2520 TMJs were collected from 861 men and 399 women (average age 37.33 ± 18.83 years). A deep learning algorithm with a convolutional neural network was developed. Data augmentation and the Adam optimizer were applied to reduce the risk of overfitting the deep-learning model. The prediction performances were compared between the models and human experts based on areas under the curve (AUCs). The fine-tuning model showed excellent prediction performance (AUC = 0.8775) and acceptable accuracy (approximately 77%). Comparing the AUC values of the from-scratch (0.8269) and freeze models (0.5858) showed lower performances of the other models compared to the fine-tuning model. In Grad-CAM visualizations, the fine-tuning scheme focused more on the TMJ disc when judging ADD, and the sparsity was higher than that of the from-scratch scheme (84.69% vs. 55.61%, p < 0.05). The three fine-tuned ensemble models using different data augmentation techniques showed a prediction accuracy of 83%. Moreover, the AUC values of ADD were higher when patients with TMD were divided by age (0.8549-0.9275) and sex (male: 0.8483, female: 0.9276). While the accuracy of the ensemble model was higher than that of human experts, the difference was not significant (p = 0.1987-0.0671). Learning from pre-trained weights allowed the fine-tuning model to outperform the from-scratch model. Another benefit of the fine-tuning model for diagnosing ADD of TMJ in Grad-CAM analysis was the deactivation of unwanted gradient values to provide clearer visualizations compared to the from-scratch model. The Grad-CAM visualizations also agreed with the model learned through important features in the joint disc area. The accuracy was further improved by an ensemble of three fine-tuning models using diversified data. The main benefits of this model were the higher specificity compared to human experts, which may be useful for preventing true negative cases, and the maintenance of its prediction accuracy across sexes and ages, suggesting a generalized prediction.


Assuntos
Aprendizado Profundo , Transtornos da Articulação Temporomandibular , Adolescente , Adulto , Algoritmos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Adulto Jovem
14.
Cell Rep ; 39(11): 110949, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35705045

RESUMO

Despite the ubiquitous function of macrophages across the body, the diversity, origin, and function of adrenal gland macrophages remain largely unknown. We define the heterogeneity of adrenal gland immune cells using single-cell RNA sequencing and use genetic models to explore the developmental mechanisms yielding macrophage diversity. We define populations of monocyte-derived and embryonically seeded adrenal gland macrophages and identify a female-specific subset with low major histocompatibility complex (MHC) class II expression. In adulthood, monocyte recruitment dominates adrenal gland macrophage maintenance in female mice. Adrenal gland macrophage sub-tissular distribution follows a sex-dimorphic pattern, with MHC class IIlow macrophages located at the cortico-medullary junction. Macrophage sex dimorphism depends on the presence of the cortical X-zone. Adrenal gland macrophage depletion results in altered tissue homeostasis, modulated lipid metabolism, and decreased local aldosterone production during stress exposure. Overall, these data reveal the heterogeneity of adrenal gland macrophages and point toward sex-restricted distribution and functions of these cells.


Assuntos
Glândulas Suprarrenais , Macrófagos , Monócitos , Caracteres Sexuais , Glândulas Suprarrenais/metabolismo , Animais , Feminino , Antígenos de Histocompatibilidade Classe II/genética , Contagem de Leucócitos , Macrófagos/metabolismo , Masculino , Camundongos
15.
Microbiol Resour Announc ; 11(6): e0005322, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35575490

RESUMO

Here, we report the draft genome sequence of Desemzia sp. strain C1, which was isolated from oil-contaminated soil in South Korea and produces hydrogen peroxide (H2O2). The genome of Desemzia sp. strain C1 contains genes encoding various oxidases involved in H2O2 production and resistance to oxidative stress.

17.
Sensors (Basel) ; 21(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34770673

RESUMO

This paper presents a case study of continuous productivity improvement of an automotive parts production line using Internet of Everything (IoE) data for fault monitoring. Continuous productivity improvement denotes an iterative process of analyzing and updating the production line configuration for productivity improvement based on measured data. Analysis for continuous improvement of a production system requires a set of data (machine uptime, downtime, cycle-time) that are not typically monitored by a conventional fault monitoring system. Although productivity improvement is a critical aspect for a manufacturing site, not many production systems are equipped with a dedicated data recording system towards continuous improvement. In this paper, we study the problem of how to derive the dataset required for continuous improvement from the measurement by a conventional fault monitoring system. In particular, we provide a case study of an automotive parts production line. Based on the data measured by the existing fault monitoring system, we model the production system and derive the dataset required for continuous improvement. Our approach provides the expected amount of improvement to operation managers in a numerical manner to help them make a decision on whether they should modify the line configuration or not.

18.
ACS Appl Mater Interfaces ; 13(48): 57962-57970, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34797978

RESUMO

Catalytic redox reactions have been employed to enhance colorimetric biodetection signals in point-of-care diagnostic tests, while their time-sensitive visual readouts may increase the risk of false results. To address this issue, we developed a dual photocatalyst signal amplification strategy that can be controlled by a fixed light dose, achieving time-independent colorimetric biodetection in paper-based tests. In this method, target-associated methylene blue (MB+) photocatalytically amplifies the concentration of eosin Y by oxidizing deactivated eosin Y (EYH3-) under red light, followed by photopolymerization with eosin Y autocatalysis under green light to generate visible hydrogels. Using the insights from mechanistic studies on MB+-sensitized photo-oxidation of EYH3-, we improved the photocatalytic efficiency of MB+ by suppressing its degradation. Lastly, we characterized 100- to 500-fold enhancement in sensitivity obtained from MB+-specific eosin Y amplification, highlighting the advantages of using dual photocatalyst signal amplification.


Assuntos
Materiais Biomiméticos/química , Colorimetria , Amarelo de Eosina-(YS)/análise , Azul de Metileno/química , Catálise , Teste de Materiais , Estrutura Molecular , Oxirredução , Processos Fotoquímicos , Polimerização
19.
ACS Appl Mater Interfaces ; 13(33): 38990-39002, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34379400

RESUMO

The ongoing COVID-19 pandemic has clearly established how vital rapid, widely accessible diagnostic tests are in controlling infectious diseases and how difficult and slow it is to scale existing technologies. Here, we demonstrate the use of the rapid affinity pair identification via directed selection (RAPIDS) method to discover multiple affinity pairs for SARS-CoV-2 nucleocapsid protein (N-protein), a biomarker of COVID-19, from in vitro libraries in 10 weeks. The pair with the highest biomarker sensitivity was then integrated into a 10 min, vertical-flow cellulose paper test. Notably, the as-identified affinity proteins were compatible with a roll-to-roll printing process for large-scale manufacturing of tests. The test achieved 40 and 80 pM limits of detection in 1× phosphate-buffered saline (mock swab) and saliva matrices spiked with cell-culture-generated SARS-CoV-2 viruses and is also capable of detection of N-protein from characterized clinical swab samples. Hence, this work paves the way toward the mass production of cellulose paper-based assays which can address the shortages faced due to dependence on nitrocellulose and current manufacturing techniques. Further, the results reported herein indicate the promise of RAPIDS and engineered binder proteins for the timely and flexible development of clinically relevant diagnostic tests in response to emerging infectious diseases.


Assuntos
Antígenos Virais/análise , Teste Sorológico para COVID-19/métodos , Proteínas do Nucleocapsídeo/análise , SARS-CoV-2/química , Biomarcadores/análise , Técnicas Biossensoriais , COVID-19/prevenção & controle , Celulose/química , Ensaio de Imunoadsorção Enzimática/métodos , Corantes Fluorescentes/química , Humanos , Técnicas Analíticas Microfluídicas/métodos , Biblioteca de Peptídeos , Ligação Proteica
20.
J Am Chem Soc ; 143(30): 11544-11553, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34288684

RESUMO

Exponential molecular amplification such as the polymerase chain reaction is a powerful tool that allows ultrasensitive biodetection. Here, we report a new exponential amplification strategy based on photoredox autocatalysis, where eosin Y, a photocatalyst, amplifies itself by activating a nonfluorescent eosin Y derivative (EYH3-) under green light. The deactivated photocatalyst is stable and rapidly activated under low-intensity light, making the eosin Y amplification suitable for resource-limited settings. Through steady-state kinetic studies and reaction modeling, we found that EYH3- is either oxidized to eosin Y via one-electron oxidation by triplet eosin Y and subsequent 1e-/H+ transfer, or activated by singlet oxygen with the risk of degradation. By reducing the rate of the EYH3- degradation, we successfully improved EYH3--to-eosin Y recovery, achieving efficient autocatalytic eosin Y amplification. Additionally, to demonstrate its flexibility in output signals, we coupled the eosin Y amplification with photoinduced chromogenic polymerization, enabling sensitive visual detection of analytes. Finally, we applied the exponential amplification methods in developing bioassays for detection of biomarkers including SARS-CoV-2 nucleocapsid protein, an antigen used in the diagnosis of COVID-19.


Assuntos
Proteínas do Nucleocapsídeo de Coronavírus/análise , Amarelo de Eosina-(YS)/análogos & derivados , Espectrometria de Fluorescência/métodos , 3,3'-Diaminobenzidina/química , Biomarcadores/química , Catálise/efeitos da radiação , Amarelo de Eosina-(YS)/síntese química , Amarelo de Eosina-(YS)/efeitos da radiação , Fluorescência , Luz , Limite de Detecção , Oxirredução/efeitos da radiação , Fosfoproteínas/análise , Polietilenoglicóis/química , Polimerização , Estudo de Prova de Conceito , SARS-CoV-2/química
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