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1.
Plant Physiol ; 195(3): 2094-2110, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38588029

RESUMO

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.


Assuntos
Citocininas , Regulação da Expressão Gênica de Plantas , Plumbaginaceae , Citocininas/metabolismo , Citocininas/farmacologia , Plumbaginaceae/genética , Plumbaginaceae/crescimento & desenvolvimento , Plumbaginaceae/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
2.
Breast Cancer Res Treat ; 204(3): 475-484, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38191685

RESUMO

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.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética , Biópsia Líquida
3.
Opt Express ; 32(4): 5982-5995, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439312

RESUMO

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.
Chem Soc Rev ; 52(16): 5541-5562, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37519093

RESUMO

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.

5.
Opt Express ; 31(19): 30615-30626, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710601

RESUMO

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.

6.
Opt Express ; 30(11): 19081-19089, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221694

RESUMO

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.

7.
Chemistry ; 28(39): e202200981, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35487846

RESUMO

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.


Assuntos
Alcinos , Ácidos Borônicos , Elétrons , Indicadores e Reagentes
8.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35522737

RESUMO

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.


Assuntos
Ésteres , Hidrazinas , Ésteres/química , Radicais Livres , Hidrazinas/química
9.
Exp Brain Res ; 240(2): 439-451, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34787685

RESUMO

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.


Assuntos
Eletroencefalografia , Humanos , Matemática
10.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806037

RESUMO

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.


Assuntos
Melhoramento Vegetal , Tolerância ao Sal , Bactérias , Produtos Agrícolas , Raízes de Plantas , Rizosfera , Tolerância ao Sal/fisiologia , Solo , Microbiologia do Solo
11.
Angew Chem Int Ed Engl ; 61(16): e202200371, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35174596

RESUMO

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.


Assuntos
Ácidos de Lewis , Ácidos Fosfóricos , Catálise , Estereoisomerismo
12.
Proteins ; 89(4): 409-415, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33244777

RESUMO

This article combines the principal component analysis (PCA) with persistent homology for applications in biomolecular data analysis. We extend the technique of persistent homology to localized weighted persistent homology to fit the properties of molecules. We introduce this novel PCA in the study of the folding process of residues 1 to 28 of amyloid beta peptide in solution. We are able to determine seven metastable states of amyloid beta 1 to 28 using homology of dimension 2, corresponding to seven local minimums in the free energy landscape. We also give the transition information between the seven types and the disconnectivity graph. Our result is very robust under change of parameters. Furthermore persistent homology of dimension 1 also give consistent results. This method can be applied to different peptides and molecules.


Assuntos
Peptídeos beta-Amiloides , Fragmentos de Peptídeos , Homologia Estrutural de Proteína , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Bases de Dados de Proteínas , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Análise de Componente Principal , Conformação Proteica , Dobramento de Proteína , Termodinâmica
13.
J Am Chem Soc ; 143(44): 18527-18535, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34704444

RESUMO

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.

14.
Genome ; 64(7): 719-733, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33356862

RESUMO

Due to the specific properties of the marine environment, marine microorganisms have exclusive physicochemical characteristics that are different from those of terrestrial microorganisms, which can produce various secondary metabolites (SMs) with considerable structural diversity and biological activity. In this study, three strains of coepiphytic Aspergillus with potential antibacterial activities, A7 (Aspergillus flavus), B27 (Aspergillus flavipes), and R12 (Aspergillus sydowii), were isolated from the South China Sea. Via the Illumina MiSeq sequencing platform, the genomes of the three strains were sequenced, and genome comparison showed the highest diversity of the biosynthetic gene clusters (BGCs) in A7. In addition, a comparison of physiological and genomic characteristics between A7 and other A. flavus strains demonstrated the superior environmental adaptability of A7, which is apparently consistent with the genetic richness of BGCs. By assigning reads to known BGCs, putative BGCs were allocated in A7 that corresponded to various SMs, including naphthopyrone, pyranonigrin E, and cyclopiazonic acids. Based on gene homology analysis, we surmise that a region is involved in the biosynthesis of ustiloxin-like RiPPs, a less thoroughly studied SM in fungi. Our results provide genetic information for the investigation of marine Aspergillus spp., which may help to elucidate their chemical diversity and adaptive strategies.


Assuntos
Aspergillus flavus , Genoma Fúngico , Antibiose , Organismos Aquáticos , Aspergillus/genética , Aspergillus flavus/genética , China , Família Multigênica
15.
J Org Chem ; 86(19): 13618-13630, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34498883

RESUMO

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.


Assuntos
Aporfinas , Paládio , Catálise
16.
Org Biomol Chem ; 19(21): 4752-4759, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33978053

RESUMO

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.

17.
Psychol Res ; 85(4): 1662-1672, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32472236

RESUMO

The present study aimed to investigate whether there are basic numerical processing deficits in high math anxiety (HMA) individuals and examine the effects of cognitive inhibition on the performance of high and low math anxiety (LMA) individuals. 35 undergraduate students were recruited to perform a numerical comparison task, a numerical Stroop task, a dot comparison task, and a dot Stroop task. Results showed the following: (1) Compared with LMA group, HMA group reacted more slowly and exhibited more fixation counts in non-symbolic representation task. (2) Inhibition condition significantly increased HMA individuals' fixation durations, whereas the fixation durations of LMA individuals were similar between inhibition and non-inhibition condition. The results demonstrated that MA might temporarily occupy individuals' working memory resources. (3) In non-symbolic representation task, the effect of numerical ratio on fixation counts was larger for HMA group than that for LMA group under inhibition condition, indicating MA might arise from a basic level deficit in numerosity processing.


Assuntos
Ansiedade/psicologia , Cognição/fisiologia , Conceitos Matemáticos , Estudantes/psicologia , Humanos , Inibição Psicológica , Masculino , Matemática , Teste de Stroop , Pensamento/fisiologia , Adulto Jovem
18.
Opt Express ; 28(14): 20032-20039, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32680071

RESUMO

It is well known that in general the spectrum of a beam that is generated by a partially coherent source will change on propagation. Here we derive necessary and sufficient conditions under which the often-used Gaussian Schell-model sources can produce beams whose normalized spectrum is invariant everywhere, or is invariant just along the beam axis. These sources are not necessarily quasi-homogeneous or obeying the scaling law.

19.
Opt Express ; 28(24): 35937-35945, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379699

RESUMO

We present a class of broadband electromagnetic Gaussian Schell-model sources whose state of polarization is both uniform and identical for all frequencies, but whose far-zone polarization properties strongly depend on wavelength. Also, these sources can produce beams whose polarized portion is always linearly polarized but with a polarization angle that evolves on propagation. Our results offer new insights into the behavior of broadband partially coherent sources.

20.
J Org Chem ; 83(22): 14210-14217, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30351940

RESUMO

Direct and rapid construction of carbazoles has been successfully developed via carbene-catalyzed oxidative formal [4 + 2] annulation of enals with 2-methyl-3-oxoacetate indoles. This metal-free reaction features a broad substrate scope, features good functional-group tolerance, proceeds under mild conditions, and can be easily scaled up.

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