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1.
BMC Plant Biol ; 24(1): 244, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38575936

RESUMO

BACKGROUND: This study aims to decipher the genetic basis governing yield components and quality attributes of peanuts, a critical aspect for advancing molecular breeding techniques. Integrating genotype re-sequencing and phenotypic evaluations of seven yield components and two grain quality traits across four distinct environments allowed for the execution of a genome-wide association study (GWAS). RESULTS: The nine phenotypic traits were all continuous and followed a normal distribution. The broad heritability ranged from 88.09 to 98.08%, and the genotype-environment interaction effects were all significant. There was a highly significant negative correlation between protein content (PC) and oil content (OC). The 10× genome re-sequencing of 199 peanut accessions yielded a total of 631,988 high-quality single nucleotide polymorphisms (SNPs), with 374 significant SNP loci identified in association with the nine traits of interest. Notably, 66 of these pertinent SNPs were detected in multiple environments, and 48 of them were linked to multiple traits of interest. Five loci situated on chromosome 16 (Chr16) exhibited pleiotropic effects on yield traits, accounting for 17.64-32.61% of the observed phenotypic variation. Two loci on Chr08 were found to be strongly associated with protein and oil contents, accounting for 12.86% and 14.06% of their respective phenotypic variations, respectively. Linkage disequilibrium (LD) block analysis of these seven loci unraveled five nonsynonymous variants, leading to the identification of one yield-related candidate gene and two quality-related candidate genes. The correlation between phenotypic variation and SNP loci in these candidate genes was validated by Kompetitive allele-specific PCR (KASP) marker analysis. CONCLUSIONS: Overall, molecular markers were developed for genetic loci associated with yield and quality traits through a GWAS investigation of 199 peanut accessions across four distinct environments. These molecular tools can aid in the development of desirable peanut germplasm with an equilibrium of yield and quality through marker-assisted breeding.


Assuntos
Arachis , Estudo de Associação Genômica Ampla , Arachis/genética , Locos de Características Quantitativas/genética , Melhoramento Vegetal , Mapeamento Cromossômico/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
2.
Angew Chem Int Ed Engl ; 63(33): e202409120, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38770884

RESUMO

Triphenylamine[3]arenes (TPA[3]s), featuring [16]paracyclophane backbone with alternating carbon and nitrogen bridging atoms, were synthesized through a BF3 ⋅ Et2O-catalyzed cyclization reaction using triphenylamine derivatized monomers and paraformaldehyde. This molecular design yielded a series of TPA[3] macrocycles with high efficiency, with their facile derivatizations also successfully demonstrated. On account of the strong electron-donating properties of the TPA moieties, these TPA[3]s exhibit remarkable delayed fluorescence, and possess a significant affinity for iodine. Furthermore, their inherent three-fold symmetry rendered TPA[3]s as novel building blocks for the construction of extended frameworks and molecular cages. This advancement expands the versatility of discrete macrocycles into complex architectures, enhancing their applicability across a broad spectrum of applications.

3.
J Org Chem ; 87(5): 3788-3793, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35188782

RESUMO

A novel tetrahydroxydiboron and nickel chloride cocatalyzed radical cyclization cascade with a broad substrate scope and an ultrashort reaction time was developed. The mechanistic investigation indicated that the reaction might involve a homocleavage of tetrahydroxydiboron and nickel hydride intermediates. This approach enables the simple and efficient synthesis of a series of heteropolycycles.


Assuntos
Alcaloides , Níquel , Ciclização , Estereoisomerismo
4.
Angew Chem Int Ed Engl ; 61(31): e202204589, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35451151

RESUMO

A "rim-differentiated" pillar[6]arene (RD-P[6]) was obtained successfully, with the assistance of a dimeric silver trifluoroacetate template, among eight different constitutional isomers in a direct and regioselective manner. The solid-state conformation of this macrocycle could switch from the 1,3,5-alternate to a truly rim-differentiated one upon guest inclusion. This highly symmetric RD-P[6] not only hosts metal-containing molecules inside its cavity, but also can form a pillar[6]arene-C60 adduct through co-crystallization on account of donor-acceptor interactions. The development of synthetic strategies to desymmetrize pillararenes offers new opportunities for engineering complex molecular architectures and organic electronic materials.

5.
J Org Chem ; 86(9): 6879-6887, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33905251

RESUMO

A novel method for the synthesis of N-difluoromethyl-2-pyridones was described. This protocol enables the synthesis of N-difluoromethyl-2-pyridones from readily available pyridines using mild reaction conditions that are compatible with a wide range of functional groups. The preliminary mechanistic study revealed that N-difluoromethylpyridinium salts were the key intermediates to complete this conversion.


Assuntos
Piridinas , Piridonas
6.
J Integr Plant Biol ; 63(8): 1521-1537, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34038040

RESUMO

Trichomes function in plant defenses against biotic and abiotic stresses; examination of glabrous lines, which lack trichomes, has revealed key aspects of trichome development and function. Tests of allelism in 51 glabrous rice (Oryza sativa) accessions collected worldwide identified OsSPL10 and OsWOX3B as regulators of trichome development in rice. Here, we report that OsSPL10 acts as a transcriptional regulator controlling trichome development. Haplotype and transient expression analyses revealed that variation in the approximately 700-bp OsSPL10 promoter region is the primary cause of the glabrous phenotype in the indica cultivar WD-17993. Disruption of OsSPL10 by genome editing decreased leaf trichome density and length in the NIL-HL6 background. Plants with genotype OsSPL10WD-17993 /HL6 generated by crossing WD-17993 with NIL-HL6 also had fewer trichomes in the glumes. HAIRY LEAF6 (HL6) encodes another transcription factor that regulates trichome initiation and elongation, and OsSPL10 directly binds to the HL6 promoter to regulate its expression. Moreover, the transcript levels of auxin-related genes, such as OsYUCCA5 and OsPIN-FORMED1b, were altered in OsSPL10 overexpression and RNAi transgenic lines. Feeding tests using locusts (Locusta migratoria) demonstrated that non-glandular trichomes affect feeding by this herbivore. Our findings provide a molecular framework for trichome development and an ecological perspective on trichome functions.


Assuntos
Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Tricomas/crescimento & desenvolvimento , Animais , Sequência de Bases , Loci Gênicos , Genótipo , Gafanhotos/fisiologia , Oryza/parasitologia , Oryza/ultraestrutura , Fenótipo , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Transdução de Sinais , Transativadores/metabolismo , Tricomas/ultraestrutura
7.
J Org Chem ; 85(17): 11368-11374, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32820630

RESUMO

To investigate the dynamic stereochemical inversion behavior of pillar[5]arenes (P[5]s) in more detail, we synthesized a series of novel rim-differentiated P[5]s with various substituents and examined their rapid rotations by variable-temperature NMR (203-298 K). These studies revealed for the first time the barrier of "methyl-through-the-annulus" rotation (ΔG‡ = 47.4 kJ·mol-1 in acetone) and indicated that for rim-differentiated P[5]s with two types of alkyl substituents, the smaller rim typically determines the rate of rotation. However, substituents with terminal C═C or C≡C bonds give rise to lower inversion barriers, presumably as a result of attractive π-π interactions in the transition state. Finally, data on a rim-differentiated penta-methyl-penta-propargyl P[5] exhibited the complexity of the overall inversion dynamics.

8.
J Org Chem ; 84(7): 4507-4516, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30816034

RESUMO

An efficient oxydifluoroalkylation of hydroxyl-containing alkenes using a copper catalytic system has been developed. This reaction proceeded through a one-pot process of difluoroalkylation followed by nucleophilic attack of the appended hydroxyl group. This strategy has the advantages of a low-cost catalyst and broad substrate scope, which provides a facile access to various fluoroalkylated tetrahydrofurans and tetrahydropyrans.

9.
Analyst ; 144(14): 4400-4406, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31210210

RESUMO

In this work, a novel electrochemical sensor was constructed for the detection of p-nitrophenol. First, per-6-deoxy-per-6-(2-carboxy-methyl)thio-ß-cyclodextrin (AcSCD) was synthesized and used as a stabilizer agent to decorate gold nanoparticles (AcSCD-AuNPs). Subsequently, a novel electrode material was fabricated by the incorporation of AcSCD-AuNPs on mesoporous carbon (MC). Furthermore, a glassy carbon electrode electrochemical sensor modified with AcSCD-AuNPs-MC was prepared and characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Eventually, the constructed electrochemical sensor was used for the detection of p-nitrophenol by differential pulse voltammetry (DPV) experiments. The results showed that the linear response ranges are 0.1-10 µM and 10-350 µM, with a detection limit of 3.63 µg mL-1. Therefore, it is demonstrated that AcSCD-AuNPs-MC provides a synergistic effect of high catalytic activity from AuNPs and supramolecular recognition property from AcSCD effectively incorporated on MC for further electrochemical sensor applications.

10.
J Am Chem Soc ; 140(1): 74-77, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29220153

RESUMO

The synthesis of "rim-differentiated" C5-symmetric pillar[5]arenes, whose two rims are decorated with different chemical functionalities, has remained a challenging task. This is due to the inherent statistical nature of the cyclization of 1,4-disubstituted alkoxybenzenes with different substituents, which leads to four constitutional isomers with only 1/16th being rim-differentiated. Herein, we report a "preoriented" synthetic protocol based on FeCl3-catalyzed cyclization of asymmetrically substituted 2,5-dialkoxybenzyl alcohols. This yields an unprecedented 55% selectivity of the C5-symmetric tiara-like pillar[5]arene isomer among four constitutional isomers. Based on this new method, a series of functionalizable tiara-pillar[5]arene derivatives with C5-symmetry was successfully synthesized, isolated, and fully characterized in the solid state.

11.
Org Biomol Chem ; 16(16): 2841-2845, 2018 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-29620112

RESUMO

A highly regioselective copper-mediated hydrodifluoroalkylation of alkynes with ethyl bromodifluoroacetate or bromodifluoroacetamides has been developed. This strategy provides straightforward access to a variety of difluoroalkylated alkenes under mild reaction conditions with low-cost cuprous bromide and metabisulfite as reduction agents. A wide range of alkynes are applicable under these reaction conditions. The excellent functional-group compatibility and good regio- and stereoselectivities are the notable features of this transformation.

12.
J Org Chem ; 82(5): 2472-2480, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28121150

RESUMO

A general synthetic route to inherently luminescent and optically active 6-fold substituted C3-symmetric and asymmetric biphenyl-based trianglimines has been developed. The synthesis of these hexa-substituted triangular macrocycles takes advantage of a convenient method for the synthesis of symmetrically and asymmetrically difunctionalized biphenyl dialdehydes through a convergent two-step aromatic nucleophilic substitution-one-pot Suzuki-coupling reaction protocol. A modular [3+3] diamine-dialdehyde cyclocondensation reaction between both the symmetrically and asymmetrically difunctionalized-4,4'-biphenyldialdehydes with enantiomerically pure (1R,2R)-1,2-diaminocyclohexane was employed to construct the hexa-substituted triangular macrocycles. B97-D/6-311G(2d,p) density functional theory determined structures and X-ray crystallographic analysis reveal that the six substituents appended to the biphenyl legs of the trianglimine macrocycles adopt an alternating conformation not unlike the 1,3,5-alternate conformation observed for calix[6]arenes. Reduction of the imine bonds using NaBH4 afforded the corresponding 6-fold substituted trianglamine without the need to alkylate the amine nitrogen atoms which could hinder their later use as metal coordination sites and without having to introduce asymmetric carbons.

13.
Int Immunopharmacol ; 140: 112888, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39133956

RESUMO

Pancreatic cancer is characterized by an extremely poor prognosis and presents significant treatment challenges. Liver metastasis is the leading cause of death in patients with pancreatic cancer. Recent studies have highlighted the significant impact of neutrophils on tumor occurrence and progression, as well as their crucial role in the pancreatic cancer tumor microenvironment. Neutrophil infiltration plays a critical role in the progression and prognosis of pancreatic cancer. Neutrophils contribute to pancreatic cancer liver metastasis through various mechanisms, including angiogenesis, immune suppression, immune evasion, and epithelial-mesenchymal transition (EMT). Therefore, targeting neutrophils holds promise as an important therapeutic strategy for inhibiting pancreatic cancer liver metastasis. This article provides a summary of research findings on the involvement of neutrophils in pancreatic cancer liver metastasis and analyzes their potential as therapeutic targets. This research may provide new insights for the treatment of pancreatic cancer and improve the prognosis of patients with this disease.


Assuntos
Neoplasias Hepáticas , Neutrófilos , Neoplasias Pancreáticas , Microambiente Tumoral , Humanos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/tratamento farmacológico , Neutrófilos/imunologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Animais , Microambiente Tumoral/imunologia , Transição Epitelial-Mesenquimal , Infiltração de Neutrófilos/efeitos dos fármacos , Terapia de Alvo Molecular
14.
Front Neurol ; 15: 1383300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988602

RESUMO

Objective: This research endeavors to explore the relationship between serum uric acid (SUA) concentration and all-cause mortality in stroke patients. Methods: We undertook a cross-sectional analysis utilizing data derived from the National Health and Nutrition Examination Survey (NHANES) spanning 2007 to 2016. The concentrations of SUA served as the independent variable, while the dependent variable was defined as all-cause mortality in stroke patients. The quartile method was utilized to classify uric acid levels into four distinct categories. Subsequently, three models were developed, and Cox proportional hazards regression was used to assess the effect of varying uric acid concentrations on the risk of all-cause mortality among stroke patients. Results: The study included a total of 10,805 participants, of whom 395 were stroke patients. Among all populations, the group with elevated levels of uric acid (Q4) exhibited a significant association with the overall mortality risk among stroke patients in all three models (model 1 p < 0.001, model 2 p < 0.001, model 3 p < 0.001). In the male population, there was no significant correlation observed between uric acid levels and the overall mortality risk among stroke patients in model 3 (Q2 p = 0.8, Q3 p = 0.2, Q4 p = 0.2). However, within the female population, individuals with high uric acid levels (Q4) demonstrated a noteworthy association with the overall mortality risk among stroke patients across all three models (model 1 p < 0.001, model 2 p < 0.001, model 3 p < 0.001). Conclusion: This cross-sectional investigation reveals a significant correlation between SUA levels and all-cause mortality in stroke patients, with a noticeable trend observed among females. Consequently, SUA may serve as a promising biomarker for assessing the prognosis of individuals affected by stroke.

15.
Artigo em Inglês | MEDLINE | ID: mdl-39360334

RESUMO

The growing high standard of people's wear has put forward requirements for fabrics, and multifunctional fabrics have been developed precisely in response to the requirements of the times. However, the incineration of waste fabrics produces a large amount of pollutants, resulting in a massive waste of resources and environmental pollution. Herein, the degradable nanofiber yarns (NYs) with self-cleaning properties were fabricated by in situ growth of SiO2 nanoparticles on the surface of the electrospun poly(p-dioxanone) (PPDO) NYs using the Stöber method. Then, the PPDO NYs were blended with carbon fibers and the PPDO/SiO2 NYs with themselves to form the Janus PPDO fabrics, respectively. The Janus PPDO fabric offered asymmetric wettability and dual personal thermal management properties. The PPDO/C side of the Janus PPDO fabric provided 65.8 °C at 1.5 V or 58.5 °C under one sunlight intensity for radiative heating. The PPDO/SiO2 side exhibited high solar reflectivity (81.8%) and mid-infrared (MIR) emissivity (99.1%), which reduced the skin temperature by 4.6 °C, resulting in radiative cooling. Moreover, the Janus PPDO fabrics display an excellent electromagnetic interference (EMI) shielding performance (53.3 dB). Therefore, yarn-based degradable Janus fabric has a promising future in multifunctional wearable products.

16.
Anal Methods ; 15(20): 2528-2535, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37191157

RESUMO

In the present work, an electrochemical sensor based on reduced graphene oxide/ß-cyclodextrin/silver nanoparticle/polyoxometalate (RGO-CD-AgNP-POM) was developed for the simultaneous detection of uric acid (UA) and L-tyrosine (L-Tyr). First, an RGO-CD-AgNP-POM nanocomposite was synthesized via a simple photoreduction method and characterized by transmission electron microscopy (TEM), energy dispersive X-ray imaging (EDS), scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA). As an electrode material, RGO-CD-AgNP-POM showed wide linear ranges (0.5-500 µM for UA, and 1-400 µM for L-Tyr) and relatively low detection limits (0.11 µM for UA, and 0.23 µM for L-Tyr). In addition, the combination of supramolecular recognition from CD and excellent electrochemical performances from RGO, AgNPs and POM was expected to enhance the sensing performances toward UA and L-Tyr in real samples with favorable recovery ranges (99%-104%). This nanocomposite provides a new platform for developing the family of electrode materials.


Assuntos
Nanopartículas Metálicas , Nanocompostos , beta-Ciclodextrinas , Ácido Úrico/análise , Ácido Úrico/química , Prata/química , Nanopartículas Metálicas/química , Tirosina , Dopamina/análise , Nanocompostos/química
17.
Materials (Basel) ; 15(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36295205

RESUMO

The direct wave between the transceiver antenna negatively affects the dynamic range and imaging quality of ground penetrating radar (GPR). Suppressing this direct wave is a vital problem in enhancing the performance of the whole GPR system. In this paper, a Minkowski-fractal metamaterial absorber (MMA) with the resistive film is proposed in the GPR transceiver antenna to reduce the mutual coupling. The simulated and measured results indicate that this MMA has an effective wideband absorption in 1.0-8.0 GHz. And the thickness of MMA is only 0.007 λ0 (with respect to 2.0 GHz). This wideband MMA can reduce the mutual coupling of the proposed GPR transceiver antenna by an average of 10 dB. And it also mitigates the time-domain ringing problem of the transmit antenna. Real-world experiments demonstrate that the direct wave from the transmitting antenna can be reduced and the target echo arriving at the receiving antenna can be increased if this MMA is placed in the proposed transceiver antenna. This resistive film-based MMA offers great promise in realizing low-cost, compact, and lightweight GPR antennas, which can also be extended to high-frequency microwave imaging.

18.
Front Microbiol ; 13: 878800, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814656

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP), a pathogen that causes severe nosocomial infections and yields a high mortality rate, poses a serious threat to global public health due to its high antimicrobial resistance. Bacteriophages encode polysaccharide-degrading enzymes referred to as depolymerases that cleave the capsular polysaccharide (CPS), one of the main virulence factors of K. pneumoniae. In this study, we identified and characterized a new capsule depolymerase K19-Dpo41 from K. pneumoniae bacteriophage SH-KP156570. Our characterization of K19-Dpo41 demonstrated that this depolymerase showed specific activities against K19-type K. pneumoniae. K19-Dpo41-mediated treatments promoted the sensitivity of a multidrug-resistant K19-type K. pneumoniae strain to the bactericidal effect of human serum and significantly increased the survival rate of Galleria mellonella infected with K19-type K. pneumoniae. Our results provided strong primary evidence that K19-Dpo41 was not only effective in capsular typing of K19-type K. pneumoniae but promising in terms of developing new alternative therapeutic strategies against K19-type CRKP infections in the future.

19.
J Hazard Mater ; 423(Pt A): 127034, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34481393

RESUMO

A glassy carbon electrode (GCE) modified by a hybrid, macroporous carbon (MPC) functionalized with triazine bridged covalent organic polycalix[4]arenes (CalCOP) (CalCOP-MPC), has been fabricated and utilized for simultaneous detection of nitrophenols (NP). The obtained CalCOP-MPC were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS), which confirmed that MPC had functionalized with CalCOP successfully. Benefiting from the synergistic supramolecular effect of macrocyclic receptor of CalCOP and the excellent electrical properties of MPC, the anodic peaks of o-nitrophenol (o-NP), m-nitrophenol (m-NP), and p-nitrophenol (p-NP) in their mixture can be well separated by the prepared electrode. Differential pulse voltammetry (DPV) measurements at CalCOP-MPC/GCE revealed that the linear ranges of NP isomers were all 1-400 µM, and the detection limit limits were 0.383 µM, 0.122 µM, and 0.212 µM for o-NP, m-NP, and p-NP, respectively. Moreover, the prepared modified electrodes showed a relatively good selectivity and stability, implying the prospect for detecting NP in real environmental samples.


Assuntos
Carbono , Nitrofenóis , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção
20.
Org Lett ; 23(6): 2205-2211, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33635677

RESUMO

The reactivity of N-difluoromethylpyridinium salts is seldom explored because of their instability and low availability. Here we present a novel nucleophilic addition of N-difluoromethylpyridinium salts with nitroalkanes to synthesize N-CF2H-dihydropyridines and N-CHO-dihydropyridines in a highly efficient and regioselective pathway. This protocol exhibits good functional group tolerance and good to excellent yields.

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