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1.
Small Methods ; : e2400155, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781604

RESUMEN

Microfluidic Paper-based Analytical Devices (µPADs) have emerged as a new class of microfluidic systems, offering numerous advantages over traditional microfluidic chips. These advantages include simplicity, cost-effectiveness, stability, storability, disposability, and portability. As a result, various designs for different types of assays are developed and investigated. In recent years, µPADs are combined with conventional detection methods to enable rapid on-site detection, providing results comparable to expensive and sophisticated large-scale testing methods that require more time and skilled personnel. The application of µPAD techniques is extensive in environmental quality control/analysis, clinical diagnosis, and food safety testing, paving the way for on-site real-time diagnosis as a promising future development. This review focuses on the recent research advancements in the design, fabrication, material selection, and detection methods of µPADs. It provides a comprehensive understanding of their principles of operation, applications, and future development prospects.

2.
Plant Physiol ; 195(3): 2094-2110, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38588029

RESUMEN

Salt gland is an epidermal Na+ secretory structure that enhances salt resistance in the recretohalophyte sea lavender (Limonium bicolor). To elucidate the salt gland development trajectory and related molecular mechanisms, we performed single-cell RNA sequencing of L. bicolor protoplasts from young leaves at salt gland initiation and differentiation stages. Dimensionality reduction analyses defined 19 transcriptionally distinct cell clusters, which were assigned into 4 broad populations-promeristem, epidermis, mesophyll, and vascular tissue-verified by in situ hybridization. Cytokinin was further proposed to participate in salt gland development by the expression patterns of related genes and cytological evidence. By comparison analyses of Single-cell RNA sequencing with exogenous application of 6-benzylaminopurine, we delineated 5 salt gland development-associated subclusters and defined salt gland-specific differentiation trajectories from Subclusters 8, 4, and 6 to Subcluster 3 and 1. Additionally, we validated the participation of TRIPTYCHON and the interacting protein Lb7G34824 in salt gland development, which regulated the expression of cytokinin metabolism and signaling-related genes such as GLABROUS INFLORESCENCE STEMS 2 to maintain cytokinin homeostasis during salt gland development. Our results generated a gene expression map of young leaves at single-cell resolution for the comprehensive investigation of salt gland determinants and cytokinin participation that helps elucidate cell fate determination during epidermis formation and evolution in recretohalophytes.


Asunto(s)
Citocininas , Regulación de la Expresión Génica de las Plantas , Plumbaginaceae , Citocininas/metabolismo , Citocininas/farmacología , Plumbaginaceae/genética , Plumbaginaceae/crecimiento & desarrollo , Plumbaginaceae/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
3.
Opt Express ; 32(4): 5982-5995, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439312

RESUMEN

This study investigates the bidirectional transmission of a partially coherent flat-topped beam in a turbulent atmosphere and plasma. Analytical formulas for the intensity distribution and M2 factor are derived based on the optical transmission matrix, Collins formula, and second moment theory with Wigner distribution function. Numerical results show that the beam order and transverse spatial coherence width can be selected appropriately to mitigate turbulence and plasma induced evolution properties. The partially coherent flat-topped beam propagation through a turbulent atmosphere and plasma of the forward transmission effect on the intensity distribution and M2 factor are smaller than that of the reverse transmission. Under the same conditions, the M2 factor of a partially coherent flat-topped beam is smaller than the Gaussian beam in bidirectional transmission. Our results can be used in long-distance free-space optical communications.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38409719

RESUMEN

BACKGROUND: As a malignant tumor, osteosarcoma (OS) ranks first place among adolescent cancers and is susceptible to developing resistance to chemotherapeutic agents. Differently, traditional Chinese medicine (TCM) has multiple pharmacodynamic targets and complex biological components, which can inhibit tumor survival and drug resistance and gradually play an important role in the treatment of sarcoma. METHODS: This study is to systematically evaluate the safety and efficacy of TCM combined with chemotherapy performed in the clinical treatment of OS. Based on multiple mainstream databases, eleven articles on the relationship between natural products and chemotherapy involving 656 patients were selected from all the literature published as of June 2022. Revman 5.4 software was used for a comprehensive search analysis, supplemented by established exclusion criteria, the Jadad scale, and the evaluation methods provided by Cochrane. RESULTS: The efficiency of TCM combined with chemotherapy was significantly increased compared with chemical drugs alone [OR=2.56, 95% CI (1.36,4.79), Z=2.92, P=0.003]. Meanwhile, the adverse reactions such as nausea and vomiting, hepatotoxicity, and hematological changes caused by chemical drugs were alleviated correspondingly. CONCLUSION: This study indicates that the mode of TCM combined with chemotherapy sheds light on the clinical treatment of OS, which is much better than the one-way mode.

5.
J Imaging Inform Med ; 37(3): 1023-1037, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38351222

RESUMEN

Autism spectrum disorder (ASD) is a pervasive brain development disease. Recently, the incidence rate of ASD has increased year by year and posed a great threat to the lives and families of individuals with ASD. Therefore, the study of ASD has become very important. A suitable feature representation that preserves the data intrinsic information and also reduces data complexity is very vital to the performance of established models. Topological data analysis (TDA) is an emerging and powerful mathematical tool for characterizing shapes and describing intrinsic information in complex data. In TDA, persistence barcodes or diagrams are usually regarded as visual representations of topological features of data. In this paper, the Regional Homogeneity (ReHo) data of subjects obtained from Autism Brain Imaging Data Exchange (ABIDE) database were used to extract features by using TDA. The average accuracy of cross validation on ABIDE I database was 95.6% that was higher than any other existing methods (the highest accuracy among existing methods was 93.59%). The average accuracy for sampling with the same resolutions with the ABIDE I on the ABIDE II database was 96.5% that was also higher than any other existing methods (the highest accuracy among existing methods was 75.17%).


Asunto(s)
Trastorno del Espectro Autista , Humanos , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/epidemiología , Imagen por Resonancia Magnética , Bases de Datos Factuales , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Niño , Algoritmos
6.
Breast Cancer Res Treat ; 204(3): 475-484, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38191685

RESUMEN

PURPOSE: Serum microRNA (miRNA) holds great potential as a non-invasive biomarker for diagnosing breast cancer (BrC). However, most diagnostic models rely on the absolute expression levels of miRNAs, which are susceptible to batch effects and challenging for clinical transformation. Furthermore, current studies on liquid biopsy diagnostic biomarkers for BrC mainly focus on distinguishing BrC patients from healthy controls, needing more specificity assessment. METHODS: We collected a large number of miRNA expression data involving 8465 samples from GEO, including 13 different cancer types and non-cancer controls. Based on the relative expression orderings (REOs) of miRNAs within each sample, we applied the greedy, LASSO multiple linear regression, and random forest algorithms to identify a qualitative biomarker specific to BrC by comparing BrC samples to samples of other cancers as controls. RESULTS: We developed a BrC-specific biomarker called 7-miRPairs, consisting of seven miRNA pairs. It demonstrated comparable classification performance in our analyzed machine learning algorithms while requiring fewer miRNA pairs, accurately distinguishing BrC from 12 other cancer types. The diagnostic performance of 7-miRPairs was favorable in the training set (accuracy = 98.47%, specificity = 98.14%, sensitivity = 99.25%), and similar results were obtained in the test set (accuracy = 97.22%, specificity = 96.87%, sensitivity = 98.02%). KEGG pathway enrichment analysis of the 11 miRNAs within the 7-miRPairs revealed significant enrichment of target mRNAs in pathways associated with BrC. CONCLUSION: Our study provides evidence that utilizing serum miRNA pairs can offer significant advantages for BrC-specific diagnosis in clinical practice by directly comparing serum samples with BrC to other cancer types.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Humanos , Femenino , MicroARNs/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Perfilación de la Expresión Génica , Biomarcadores de Tumor/genética , Biopsia Líquida
7.
PeerJ ; 11: e16204, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37846308

RESUMEN

Sumoylation is a reversible post-translational modification that regulates certain significant biochemical functions in proteins. The protein alterations caused by sumoylation are associated with the incidence of some human diseases. Therefore, identifying the sites of sumoylation in proteins may provide a direction for mechanistic research and drug development. Here, we propose a new computational approach for identifying sumoylation sites using an encoding method based on topological data analysis. The features of our model captured the key physical and biological properties of proteins at multiple scales. In a 10-fold cross validation, the outcomes of our model showed 96.45% of sensitivity (Sn), 94.65% of accuracy (Acc), 0.8946 of Matthew's correlation coefficient (MCC), and 0.99 of area under curve (AUC). The proposed predictor with only topological features achieves the best MCC and AUC in comparison to the other released methods. Our results suggest that topological information is an additional parameter that can assist in the prediction of sumoylation sites and provide a novel perspective for further research in protein sumoylation.


Asunto(s)
Biología Computacional , Sumoilación , Humanos , Biología Computacional/métodos , Proteínas/química , Procesamiento Proteico-Postraduccional
8.
Opt Express ; 31(19): 30615-30626, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37710601

RESUMEN

Scintillation is an important problem for laser beams in free space optical (FSO) communications. We derived the analytical expressions for the scintillation index of a Gaussian Schell-model beam with cross phase propagation in a turbulent atmosphere. The numerical results show that the quadratic phase can be used to mitigate turbulence-induced scintillation, and the effects of the turbulent strength and beam parameters at the source plane on the scintillation index are analyzed. The variation trend of the experimentally measured scintillation index is consistent with the numerical results. Our results are expected to be useful for FSO communications.

9.
Org Lett ; 25(32): 5984-5988, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37548642

RESUMEN

A novel oxidative cleavage and fluoromethylthiolation reaction of C═C bonds has been developed that represents the first and general method for the preparation of mono-, di-, and trifluoromethylthioesters from alkenes. The protocol features excellent product selectivity and substrate suitability. Various observations suggested that the protocol proceeded via a two-step radical process and that aldehyde was the key intermediate. What's more meaningful is that this route provides a new direction for converting alkenes into higher-value-added carbonyl-containing chemicals.

10.
Chem Soc Rev ; 52(16): 5541-5562, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37519093

RESUMEN

Direct substitution of readily available alcohols is recognized as a key research area in green chemical synthesis. Starting from simple racemic secondary alcohols, the achievement of catalytic enantioconvergent transformations of the substrates will be highly desirable for efficient access to valuable enantiopure compounds. To accomplish such attractive yet challenging transformations, the strategy of the enantioconvergent borrowing hydrogen methodology has proven to be uniquely effective and versatile. This review aims to provide an overview of the impressive progress made on this topic of research that has only thrived in the past decade. In particular, the conversion of racemic secondary alcohols to enantioenriched chiral amines, N-heterocycles, higher-order alcohols and ketones will be discussed in detail.

11.
Opt Express ; 30(11): 19081-19089, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36221694

RESUMEN

The conventional scintillation, or intensity fluctuation, that occurs in random electromagnetic beams is just one member of a broader class of four interconnected, polarization-resolved scintillations. We examine these generalized scintillations, called Stokes scintillations, that occur when two stochastic electromagnetic beams are made to interfere in Young's experiment. We find that the magnitude of the conventional scintillation can be decreased, within certain limits, at the expense of an increase of one or more of the other Stokes scintillations. For certain applications however, it may be beneficial to suppress the latter.

12.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35806037

RESUMEN

Saline soils are a major challenge in agriculture, and salinization is increasing worldwide due to climate change and destructive agricultural practices. Excessive amounts of salt in soils cause imbalances in ion distribution, physiological dehydration, and oxidative stress in plants. Breeding and genetic engineering methods to improve plant salt tolerance and the better use of saline soils are being explored; however, these approaches can take decades to accomplish. A shorter-term approach to improve plant salt tolerance is to be inoculated with bacteria with high salt tolerance or adjusting the balance of bacteria in the rhizosphere, including endosymbiotic bacteria (living in roots or forming a symbiont) and exosymbiotic bacteria (living on roots). Rhizosphere bacteria promote plant growth and alleviate salt stress by providing minerals (such as nitrogen, phosphate, and potassium) and hormones (including auxin, cytokinin, and abscisic acid) or by reducing ethylene production. Plant growth-promoting rhizosphere bacteria are a promising tool to restore agricultural lands and improve plant growth in saline soils. In this review, we summarize the mechanisms of plant growth-promoting bacteria under salt stress and their applications for improving plant salt tolerance to provide a theoretical basis for further use in agricultural systems.


Asunto(s)
Fitomejoramiento , Tolerancia a la Sal , Bacterias , Productos Agrícolas , Raíces de Plantas , Rizosfera , Tolerancia a la Sal/fisiología , Suelo , Microbiología del Suelo
13.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35522737

RESUMEN

A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in functional materials and medicinal chemistry, this approach would find broad applications.


Asunto(s)
Ésteres , Hidrazinas , Ésteres/química , Radicales Libres , Hidrazinas/química
14.
Chemistry ; 28(39): e202200981, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35487846

RESUMEN

A new class of electrophilic monofluoromethylselenolation reagents, Se-(fluoromethyl) benzenesulfonoselenoates, has been developed. They can be readily prepared from sodium benzenesulfinates, Se powder and ClCFH2 in one step under mild reaction conditions. Se-(fluoromethyl) benzenesulfonoselenoates are efficient electrophilic monofluoromethylselenolation reagents for a wide range of nucleophiles including indole, 6-azaindole, pyrrole, thiophene, electron-rich arene, aryl boronic acid and alkyne. The monofluoromethylselenolation approach features mild and environmentally friendly reaction conditions, good tolerance of various functional groups, and broad substrate scope.


Asunto(s)
Alquinos , Ácidos Borónicos , Electrones , Indicadores y Reactivos
15.
Angew Chem Int Ed Engl ; 61(16): e202200371, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35174596

RESUMEN

We present herein a highly efficient atroposelective synthesis of axially chiral 1,1'-bipyrroles bearing an N-N linkage from simple hydrazine and 1,4-diones. Further product derivatizations led to axially chiral bifunctional compounds with high potential in asymmetric catalysis. For this chrial phosphoric acid (CPA)-catalyzed double Paal-Knorr reaction, an intriguing Fe(OTf)3 -induced enantiodivergence was also observed.


Asunto(s)
Ácidos de Lewis , Ácidos Fosfóricos , Catálisis , Estereoisomerismo
16.
Exp Brain Res ; 240(2): 439-451, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34787685

RESUMEN

In this study, to investigate the influence of numerical surface forms on strategy execution in subtraction and addition, 25 college students were required to perform a mental arithmetic task. Behavioral and electroencephalography responses were recorded to explore the stages of strategy execution. Arithmetic problems were presented within 11-20 by Arabic, Chinese and English numerals, respectively. The results showed that, compared with Arabic and Chinese numerals, participants had longer RTs under the condition of English numerals. English numerals induced stronger N100, P200 and P300 amplitudes, and longer latency in P200 and P300 amplitudes than in other conditions. These findings indicated that numerical surface forms affected the execution of mental arithmetic strategies, with Chinese and English numerals being processed deeper in the brain. Especially, the English digital word form occupied more psychological resources, and it was activated more in the frontal area and the parietal area, which would obviously hinder the processing of arithmetic information.


Asunto(s)
Electroencefalografía , Humanos , Matemática
17.
Front Plant Sci ; 12: 745422, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34956255

RESUMEN

Salt-resistant plants have different mechanisms to limit the deleterious effects of high salt in soil; for example, recretohalophytes secrete salt from unique structures called salt glands. Salt glands are the first differentiated epidermal structure of the recretohalophyte sea lavender (Limonium bicolor), followed by stomata and pavement cells. While salt glands and stomata develop prior to leaf expansion, it is not clear whether these steps are connected. Here, we explored the effects of the five phytohormones salicylic acid, brassinolide, methyl jasmonate, gibberellic acid, and abscisic acid on the development of the first expanded leaf of L. bicolor and its potential connection to salt gland, stomata, and pavement cell differentiation. We calculated the total number of salt glands, stomata, and pavement cells, as well as leaf area and pavement cell area, and assessed the correlations between these parameters. We detected strong and positive correlations between salt gland number and pavement cell area, between stomatal number and pavement cell area, and between salt gland number and stomatal number. We observed evidence of coupling between the development of salt glands, stomata, and pavement cells in L. bicolor, which lays the foundation for further investigation of the mechanism behind salt gland development.

18.
J Am Chem Soc ; 143(44): 18527-18535, 2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34704444

RESUMEN

Organic optoelectronic functional materials featuring circularly polarized emission and persistent luminescence represent a novel research frontier and show promising applications in data encryption, displays, biological imaging, and so on. Herein, we present a simple and universal approach to achieve circularly polarized organic phosphorescence (CPP) from amorphous copolymers by the incorporation of axial chiral chromophores into polymer chains via radical cross-linked polymerization. Our experimental data reveal that copolymers (R/S)-PBNA exhibit a maximum CPP efficiency of 30.6% and the largest dissymmetric factor of 9.4 × 10-3 and copolymers (R/S)-PNA show the longest lifetime of 0.68 s under ambient conditions. Given the CPP property of these copolymers, their potential applications in multiple information encryption and displays are demonstrated, respectively. These findings not only lay the foundation for the development of amorphous polymers with superior CPP but also expand the outlook of room-temperature phosphorescent materials.

19.
J Org Chem ; 86(19): 13618-13630, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34498883

RESUMEN

Reported herein is an intramolecular dehydrogenative coupling of two inert aryl C-H bonds for the synthesis of aporphine analogues. The process represents a novel tool for the preparation of aporphines via palladiun-catalyzed C-H bond activation. The present reaction is compatible with various functional groups, and the coupling products have been further applied for the synthesis of natural products aporphine and zenkerine.


Asunto(s)
Aporfinas , Paladio , Catálisis
20.
Org Biomol Chem ; 19(21): 4752-4759, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-33978053

RESUMEN

A novel photocatalyzed cross-dehydrogenative coupling reaction of N-Boc-tetrahydroisoquinolines with α,ß-unsaturated ketones has been developed. This research provides an easy access to a variety of C1-substituted tetrahydroisoquinolines, which can be further transformed into benzo[a]-quinolizine-2-ones, the skeletons of natural products with a wide range of biological activities. The load of the photocatalyst is low and the oxidant is inexpensive and less toxic.

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